DAYLIGHTING Magazine issue 4 May/June 2017

Issue 4 May/Jun 2017

DESIGN & TECHNOLOGY FOR BETTER BUILDINGS

IN THIS ISSUE:

Daylighting at work CLIMATE BASED DAYLIGHT MODELLING BIM GLASS ROOFLIGHTS DAYLIGHTING INNOVATIONS AND MORE

Christies Auction House

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CONTENTS

REGULARS 05

Editor’s Comment

06

Industry news

10

FEATURES

Daylighting in the workplace Chris Chaney of Sunsquare on why daylighting should be a key factor in workplace design.

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NARM Daylight Diary

Company profile Filon Products – celebrating 60 years as an innovator in GRP

Light Transmittance & Design

28

The Menil Collection, Houston, Texas

41

Twitterings What’s trending on social media?

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More about DAYLIGHTING Magazine Forthcoming features and information for advertisers & contributors

WEBSITE www.daylightingmag.co.uk

Glass Rooflights • New LED-assisted rooflight - p28 • Flat Glass rooflights - p31 • World’s first curved glass rooflight for flat roofs - p34

Daylight & Sunlight Amenity Studies Dan Tapscott sheds light on their importance as part of the planning process

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Rooflights & BIM Chris Lister of Jet Cox looks at how BIM is benefiting the rooflighting industry

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Translucent Panel Systems Architectural Journalist Gideon Sykes looks at translucent panel systems and their applications and advantages

AD SALES Miki Bennett adsales@bennettand partners.co.uk Tel: 01295 770833 DESIGN/PRODUCTION Jemma Pentney jemma@bennettand partners.co.uk Tel: 01295 770833

John Godley of Hambleside Danelaw discusses the need to use accurate light transmittance data

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Climate-Based Daylight Modelling

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Daylighting icons

EDITOR Paul Bennett paul@daylightingmag.co.uk Tel: 01295 770833 Mobile: 07900 895110

Duncan Cox of Thornton Thomasetti gives an introduction to Climate-Based Daylight Modelling and Parametric Analysis

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Bennett & Partners Pure Offices Lake View House Tournament Fields Warwick CV34 6RG United Kingdom TEL: +44 (0)1295 770833

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New Projects

Updates from the UK’s influential trade association for rooflight manufacturers

DAYLIGHTING is published by:

CIRCULATION Daylighting is available by email, free of charge to subscribers. Our database currently numbers over 6,000 UK architects, specifiers, contractors, consultants and roofing professionals.

Full details are available on our website. www.daylightingmag.com

All rights reserved. No part of this publication may be reproduced or transmitted without the consent of the publisher. While every effort is made to ensure the accuracy of content, the publisher does not accept liability for errors.

The views expressed by contributors are not necessarily those of the editor or publisher.

This publication contains editorial photographs which may have been supplied and paid for by suppliers. Full terms and conditions can be found on our website.

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Glass Recycling Jane Embury of Wrightstyle suggests the UK should have a glass recycling week to promote awareness

www.daylightingmag.co.uk

Front Cover: Siemens Academy NTAR, Northampton.

Translucent cladding by Rodeca. See page 17.

May/Jun 2017

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EDITOR’S COMMENT

Daylighting is a global issue with global implications Here we are on issue 4 already.

I’m delighted to say that it’s the biggest so far, thanks to a growing band of excellent editorial contributors and advertisers.

My involvement in the construction industry and daylighting in particular, has been largely focused on the UK marketplace, having worked with a variety of manufacturers and service providers over the years.

This being the case, the scope and reach of DAYLIGHTING Magazine has been developed for a predominantly UK-based readership.

I have therefore been surprised on studying our online stats, that we are gaining readers from all over the world - in addition to those of you who receive our e-mail and social media links – such is the power of digital publishing.

So first of all, I would like to say a big welcome to our readers in Europe, the

Issue 2 Jan/Feb 2017

DESIGN & TECHNOLOGY FOR BETTER BUILDINGS

Passivhaus DAYLIGHTING & HEALTH PATENT GLAZING NON-FRAGILITY GLAZING INNOVATION AND MORE

www.daylightingmag.co.uk

Americas, Africa, Asia and Australasia.

My understanding and belief is that the UK is a leader in design and technology for better buildings, so I hope that we can contribute to spreading the word for UK technology beyond our shores.

I also hope that by becoming a platform for sharing ideas and technologies on a global basis, we can extend our contribution to the global case for effective daylighting in buildings.

Paul Bennett paul@daylightingmag.co.uk

Let me reassure our UK advertisers that we will always maintain our strong commitment to the domestic UK market whilst at the same time being aware of our relatively small (approximately 11%) but growing readership outside the UK. The aim, as we move forward, will be to continue to grow our readership in the UK and around the world – and to draw on a broader range of editorial content that will be of interest to all our readers.

Don’t forget, back issues are always available to read on-line at daylightingmag.co.uk Previous issues of DAYLIGHTING Magazine will be available on-line indefinitely. So you can refer back to old issues whenever you like.

It’s also on our ‘to-do’ list to set up a features index, so if you can’t remember in which issue you read that fascinating feature about XYZ, you’ll be able to find it in a moment.

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INDUSTRY NEWS

Architects firms ‘missing out on tax relief’ With a wave of innovation sweeping the industry, architects could be missing out on tax relief, according to the UK’s leading R&D tax credit experts Jumpstart.

It says that many firms are unaware that they may be eligible for R&D tax relief because in the past they have largely relied on traditional techniques with little or no research and development involved. However with many companies now experimenting with new techniques and materials, they may be able to claim significant amounts in tax relief to help offset the cost.

Government records show that just 2% of R&D tax relief claims are from the construction industry, yet it accounts for over 10% of corporation tax returns.

In the year to March 2015, construction firms made 480 successful claims and received £35m in tax relief. Similarly the real estate sector made just 45 successful claims – a negligible proportion – yet it accounts

for over 5% of corporation tax returns. There are no specific figures for architecture firms.

Ian Wolfendale of Jumpstart says: “Until now architecture firms have understandably preferred to stick to the tried and tested. While we have seen plenty of exciting designs, innovations have focused more on the look and style rather than the underlying techniques.

“Now a range of pressures is driving innovation – the need to deliver more units more quickly, and to improve sustainability, rising materials costs and the shortage of skilled labour which is likely to get worse after the UK leaves the EU. New materials and technologies could offer solutions, therefore we are seeing a lot more research and development within these industries.”

Projects which may qualify for R&D tax relief may include: • developing new or improved modular construction techniques • developing new or improved

building materials • substituting one material for another – such as using wood where only concrete has been used before • extending the limits of what can be done using existing materials • energy efficiency systems • acoustic dampening, isolation or distribution within a space Ian Wolfendale adds: “In general, projects which will qualify for tax relief are those which are beyond the bounds of existing knowledge, where the existing data and design rules do not apply, or which involve experimenting or prototyping.

“Companies involved in such innovations need to ensure that they claim their full entitlement in R&D tax relief. However the rules are complex so it is best to speak to an expert and get advice on your own particular case.” www.jumpstartuk.co.uk

FAKRO to sponsor BMF Conference For the third BMF All-Industry conference in the series, FAKRO are headline sponsors.

This year’s conference is being held in the Five Star Intercontinental hotel in Budapest 15th – 18th June and FAKRO will be playing a leading role in the event again.

The conference provides an educational programme to tackle issues the industry is currently facing, with FAKRO Commercial Director Dave Robertson proudly welcoming everyone and beginning

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the process of a weekend of interaction and discussion.

There will be opportunity for merchants and suppliers to network over the 4 days. A programme of events and social activities will take place and, in addition, lead sponsors FAKRO will have a feature stand providing the opportunity to showcase their latest products, designs and manufacturing techniques. www.fakro.co.uk www.bmfconference.co.uk/budapest/

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INDUSTRY NEWS

WANTED: FEMALE ARCHITECTS Leading UK architect calls for more women to join the industry Award-winning architect Simone de Gale is passionate about everything she does - and right now, she’s using that passion to encourage other women into the industry.

The 30-something born and bred Londoner scooped the coveted Architect of the Year trophy at the recent Women in Construction Awards.

Simone believes the time is right for advocating women to consider joining the UK construction industry.

case of the playing field not being level: “Just as is the case across so many industries and professions, some areas of construction are failing women in terms of pay gaps and opportunity to become partners or directors of firms, when taking time away from the practice to have children.

“It’s upsetting that even in 2017, men and women still aren’t seen as equal, despite them doing the exact same job and possessing the same qualifications and experience.”

“The numbers of women working in the construction industry have been growing steadily over the last decade or so but we are still far outnumbered by men,” she said.

Simone’s prestigious Belgravia practice has undertaken key roles in Hammersmith Flyunder project and London’s Spherical Art Gallery.

“Women tend to overlook architecture in favour for other choices, where they can apply their creativity and flair, which is a crying shame for my industry because there are so many great opportunities for the hardworking, bright and intelligent female.”

“It is vital that new blood joins our industry because we need bright new ideas, fresh thinking and an injection of energy to make UK architects the best in the world - it simply does not matter whether those ideas come from a man or woman, what matters is that those ideas do come flowing in.”

So why are more women not joining the industry? Simone believes it’s a

www.simonedegale.com

Simone de Gale – winner of the coveted Architect of the Year trophy at the recent Women in Construction Awards.

CIBSE Daylight Group Event The influential Daylight Group of the Chartered Institute of Building Services Engineers (CIBSE) is hosting talks by two eminent speakers on Wednesday 14th June at London’s National Gallery.

At 13.30, Daylighting & Lighting Consultant Ruth Kelly Waskett will present ‘Smart Glazing: The future of glass architecture?’ She will give an overview of the main types of smart glazing that are currently available and explain some of the key technical features and considerations for future applications.

www.daylightingmag.co.uk

She will also describe her recently completed study of electrochromic glazing at De Montfort University.

Following Ruth’s presentation, Rob Booth of VELUX will deliver a presentation covering Automated Solar Shading Devices.

Bookings will be accepted until the venue capacity is reached or until 10.00 hrs on Tuesday 13th June 2017, whichever comes first.

Attendance is free but tickets must be pre-booked: www.eventbrite.co.uk

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INDUSTRY NEWS

Half day Passivhaus Training Sessions The Green Register and WARM are pleased to be working together to provide four half-day technical sessions on the Passivhaus principles in 3 locations: London, Manchester and Bristol between June 2017 and February 2018.

Although their full Passivhaus training is a fantastic way to gain an in depth understanding of all aspects of Passivhaus design, some construction professionals may not have the time or resources to be able to attend the typical Passivhaus two week course.

These afternoon sessions offer insight into all the main principles i.e. what makes a good low energy, comfortable building based on the Passivhaus standard. The training is ideal for architects and other design

professionals as the focus in these courses is on design principles.

The sessions: • Fundamentals of Passivhaus • Construction for Passivhaus • Building Services for Passivhaus • Putting Passivhaus into Practice Each of these will be run by experts in the field who are actually successfully designing/ building Passivhaus in UK. Amongst others, Bill Butcher, Alan Clarke, Sally Godber, Nick Grant, Eric Parks, Marine Sanchez, Mark Siddall; and Passivhaus Certifiers Will South, Mike Roe and Peter Warm.

Assisted by Passivhaus Designers Tom Dollard and Lucy Pedler.

For dates and booking details, visit: www.greenregister.org.uk/events

10 Homeowners Win VELUX Roof Windows Ten homeowners in the UK and Ireland who have been dreaming about building a new or upgrading an existing single-storey extension in their home have won a coveted competition by leading window manufacturer VELUX®.

The competition asked homeowners to explain why roof windows would make a difference to their extension and how important a brighter environment in their home was to them.

Winners, who will receive up to four VELUX INTEGRA® solar or electric roof windows and £1,000 worth of John Lewis vouchers, came from across England, Northern Ireland, Wales, Scotland and Ireland.

Georgina Welsh from Leeds, who is expecting her first baby with husband Mark, was ‘over the moon’ when she found out she had won the VELUX

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competition. Her home is the first in the UK to be fitted with the VELUX curved glass rooflights for flat roofs.

Georgina said: “When we viewed our new house, we knew that the kitchen and dining room were quite dark and lacked natural daylight but we loved the location so went ahead with the purchase. Over time, the lack of daylight began to deter us from using the dining room and we missed the bright summer evenings we’d enjoyed so much in our old house.

We always knew we’d need to do something about it and winning the competition definitely accelerated the process. We are over the moon to have won the competition and the VELUX flat roof windows have now been installed and bring much needed light and fresh air into our home, just in time for the arrival of our baby.”

Homeowner Georgina Welsh from Leeds, one of the VELUX competition winners

www.velux.co.uk

www.daylightingmag.co.uk

22% The value of daylight less pain medication

used in daylit hospitals

What improves wellbeing in every sector? Daylight.

People do better in daylit spaces. They use up to 22% less pain medication in hospitals and recover 41% faster*. They achieve up to 25% better school test scores**. They take fewer sick days, are happier and more productive.

Whitesales are the UK’s daylighting experts. Our rooflight designs maximise any building’s environmental performance, energy usage and with increased natural light they also improve occupier wellbeing.

The right rooflights – like our most popular products, Em-Glaze and Em-Dome – control solar gain, air quality and increase daylight along with all the benefits that brings you.

41%

faster recovery in well lit hospitals

* BRE, Daylight benefits in healthcare buildings ** Heschong Mahone Group, Daylighting in Schools

Engage the experts in rooflight design. Call us on 01483 271371 or email sales@whitesales.co.uk for your free site survey and condition report.

Test scores

improve up to

25% when you let

daylight in

NEW PROJECTS Kelvin Hall, Glasgow Lareine Engineering has refurbished rooflights and louvre ventilation on Glasgow’s historic Kelvin Hall, as part of a major refurbishment of this landmark building.

The photograph shows the project after phase one was completed in 2016. www. lareineengineering.com

Private home, North London A pair of triangular rooflights were manufactured by Lonsdale for this extension to a North London home.

Architect, Simon Feneley’s asymmetric roof design, takes advantage of the sun’s position both morning and evening to create a bright living space throughout the day. www.lonsdalemetal. co.uk

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NEW PROJECTS St. Andrews Square, Edinburgh Architectural aluminium glazing systems by leading UK manufacturer Kawneer were specified for a landmark office building refurbishment in the Edinburgh New Town Conservation Area. After a two-year build by main contractor Bowmer & Kirkland, the site is now transformed, with the nine-storey building clad in stone and glass with bronze feature picture windows and bespoke Aurubis “bronze� metal fins attached to the curtain walling by Kawneer, part of the Arconic group. www.kawneer.com

Private home, South West London For this project, Zachary Pulman Design Studio commissioned five stunning bespoke rooflights from Lumen, who were able to adapt their product to a design which met his exacting requirements, in terms of sizes, appearance and operation, including concealed electric actuation and electric blinds. www.lumenrooflight. co.uk/

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May/Jun 2017

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NEW PROJECTS Kelvin Hall, Glasgow Lareine Engineering has refurbished rooflights and louvre ventilation on Glasgow’s historic Kelvin Hall, as part of a major refurbishment of this landmark building.

The photograph shows the project after phase one was completed in 2016. www. lareineengineering.com

Private home, North London A pair of triangular rooflights were manufactured by Lonsdale for this extension to a North London home.

Architect, Simon Feneley’s asymmetric roof design, takes advantage of the sun’s position both morning and evening to create a bright living space throughout the day. www.lonsdalemetal. co.uk

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ROOFLIGHTS VERTICAL GLAZING NATURAL VENTILATION SMOKE VENTILATION LOUVRE SYSTEMS ACCESS SOLUTIONS

Daylighting & ventilation from concept to installation

NEW BUILD & REFURB FOR EVERY SECTOR

With an experienced in-house design and specification department, plus our own teams of installers around the country, we are able to provide outstanding engineered daylighting and ventilation solutions for virtually any kind of project: new build or refurbishment.

Our ‘concept to installation’ approach allows continuity and close quality control over every stage of every project, to deliver excellence – every time.

Call us today to discuss how we can help to bring your next project to life.

T 01506 448140 F 01506 448141 E info@lareineengineering.com www.lareineengineering.com

O U R S TA N D A R D I S S O M U C H M O R E T H A N S TA N D A R D A L L R O O F L I G H T S W I T H L A M I N AT E D I N N E R PA N E S A S S TA N D A R D Sunsquare Limited offer a range of Rooflights including solutions for fixed units, hinged opening with electrical opening mechanism, rooftop access and walk-on Rooflights.

For more information telephone 01284 848 790, email sales@sunsquare.co.uk or visit www.sunsquare.co.uk The first and only Rooflight manufacturers to be BSI verified and awarded a Kitemark.

DAYLIGHTING AT WORK

Daylighting and the healthy workspace The health and wellbeing of staff has come to the forefront over the last 18 months.

Here Chris Chaney, Managing Director of Sunsquare, explains how daylighting should be a key factor in workplace design.

The word ‘company’ means a group of people and to keep a company happy and healthy the individuals must have a sense of wellbeing.

On average, we spend 90% of our time indoors particularly at work and a healthy work space is essential to that feeling of wellbeing.

There have been many reports over the past few years on biophilia, the hypothesis which suggests that humans seek connections with nature, and its positive effects on our health, wellbeing and productivity. The more natural our environment feels, the happier we feel.

With a growth in academic research, it has been proven that the presence of the natural elements can have a positive impact on how we feel. It has been shown that daylight, for example, has a role in maintaining our circadian rhythms.

The Well Building Standard supports this idea that health and wellbeing should be integral to the design of a building, focusing on seven key concepts of a building’s performance and human behaviour involving air, water, nourishment, light, fitness, comfort and mind.

Healthy Spaces The WELL Building standard emphasises the need for lighting to minimize disruption to the body’s circadian rhythm while enhancing

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daytime productivity and supporting good quality sleep at the end of the day. Natural light has many advantages over using artificial lights – the access to vitamin D to maintain healthy bones is just one, let alone the incontestable impact on our mental health. It is also very cost effective.

In a typical building, lighting accounts for up to 40% of energy consumption. Allowing more natural light to penetrate the building and controlling both the light and heat components of power consumption, will result in significant cost reductions.

However, using natural light doesn’t come without some issues. Glare, overheating, variability and privacy issues can all cause problems.

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DAYLIGHTING AT WORK Architects are increasingly looking for new and innovative ways to address these while increasing natural lighting resulting in a surge in demand for rooflights.

planning permission rules to provide a daylight solution even where a wall forms the boundary of the property.

Daylight it up

Rooflights work in both commercial and residential buildings and can provide an answer to dark spaces while boosting the health and wellbeing of the occupants and making them feel better about the space.

Building design now needs to control the admission of natural light into a building, reducing reliance on power consumption while creating a visually stimulating environment. Rooflights provide three times more light than the same area of vertical glazing while providing a much more even distribution of light, particularly in larger structures.

The effective area for natural lighting will only be within 6m of the wall containing a vertical window. Victorian terraces in city centres are often dark Dickensian places but can be transformed by the addition of modern rooflights to flood the interior space with natural light. Elegant changes to the appeal of a building redevelopment can be made even in a conservation area, taking a different approach to

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Make it work

Victorian terraces in city centres are often dark Dickensian places but can be transformed by the addition of modern rooflights

In 2013, The Royal Institute of British Architects launched a campaign – HomeWise – that called for government to set a minimum threshold for light (and space) in buildings which led to a new housing standard called the ‘Nationally Described Space Standard’ in 2015.

While this addressed the space issue – albeit in a voluntary capacity – it did not tackle the lighting issues.

It is hoped the WELL Building standard will lead the change in this area making daylighting possible in all buildings. www.sunsquare.co.uk

Walk-on skylights were used to help create a social space for employees and clients of this London Media Company, while offering daylight to the office space below.

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DAYLIGHTING AT WORK Siemens Academy NTAR Northampton Translucent polycarbonate cladding panels from Rodeca were specified for this national training academy to maximise natural daylight for an optimum learning environment and to show the processes within the building.

See also the front cover of this issue of DAYLIGHTING. www.rodeca.co.uk

Spire Hospital, Manchester Architectural aluminium glazing by leading UK manufacturer Kawneer was a “first point of call” for Halliday Meecham Architects for the £65 million new flagship Spire Hospital in Manchester.

Kawneer’s AA®100 SSG (Structurally Silicone Glazed) mullion-drained curtain walling, some of it curved on plan, features on the thirdstorey conference suite and is complemented by the AA®100 zone-drained capped system used elsewhere including internal screens around the reception areas. www.kawneer.com

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CLIMATE-BASED DAYLIGHT MODELLING

Climate-Based Daylight Modelling and Parametric Analysis An introduction by Duncan Cox, Senior Project Consultant, Thornton Tomasetti The benefits in capturing and controlling daylight have been central to building design throughout history.

Daylight is a basic human need, which is highlighted by the provision of transparent and translucent surfaces to all occupied spaces that we see around us. By harnessing and controlling daylight we are able to reduce energy demand and improve building user comfort.

Prior to the introduction of ClimateBased Daylight Modelling (first introduced by Mardaljevic at the 2006 CIBSE National Conference), most computational daylighting analysis involved sizing daylight apertures, based on a worst-case-day such as overcast sky conditions. While ubiquitous, the simplified method provided an overly simplistic picture of a building’s daylighting performance.

With increased computational power and improved daylighting algorithms, Climate-Based Daylight Modelling simulates all 8,760 hours of the year in a given climate, providing critical insight into how daylight will behave in a designer’s building.

Climate-Based Daylight Modelling (CBDM) interprets the data contained within meteorological datasets. These datasets contain historical weather data collected over numerous years for different geographical locations

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and will include as a minimum the following categories: temperature, relative humidity, radiation, wind, cloud cover, and illuminance. CBDM makes predictions on radiant and luminous quantities (e.g. irradiance, illuminance, radiance and luminance) using the historic climate conditions contained within the weather file. (http://climate-based-daylighting.com/ doku.php?id=academic:climate-baseddaylight-modelling). These predictions consider a building’s form, orientation and geographical location.

“As a pre-cursor to any CBDM it is prudent to interrogate and investigate the raw meteorological dataset.”

Climate Interrogation As a pre-cursor to any CBDM it is prudent to interrogate and investigate the raw meteorological dataset. These datasets typically contain hourly values for an average year. An ‘average year’ is created by applying weighting factors to various climate conditions from each hour of different years and constructing a prototypical year from the most consistent conditions. Some average years may reference five years of data while others may reference 30 years. By the law of averages, datasets with more annual records will generally show a greater ability to predict future conditions of a locality than limited data sets. An early interrogation of the raw dataset before analysis gives confirmation as to the integrity of the data.

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CLIMATE-BASED DAYLIGHT MODELLING

Bigelow Laboratory for Ocean Sciences: daylight capture can add infinite value to a space

Parametric Analysis Case Study For the purposes of this article, let’s consider a regular example building located in Birmingham, UK to demonstrate the potential of CBDM and parametric design modelling. To validate the integrity of our chosen datatset we are able to pull out graphical representations of the data contained within. Whilst these representations occasionally reveal unexpected climate trends, they will highlight whether the data is incomplete or inconsistent. The examples in figure 1 demonstrate the expected pattern in temperature and radiation for the Birmingham location, which gives us confidence in the data.

These plots also allow us to start to think about user comfort and how the location moves between a cooling and heating need.

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Figure 1: Annual Temperature and Radiation Spread from GBR_ Birmingham.035340.IWEC

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CLIMATE-BASED DAYLIGHT MODELLING Early dataset interrogation also gives design teams valuable information on how their design interacts with the climate. Using Radiance’s gendaymtx function (https://www.radiance-online. org) it is possible to calculate the sky’s radiation for each hour of the year and plot this onto a radiation sky dome. The design team can anticipate how their building will respond to

radiation and start to formulate ideas around shading, massing and glazing strategies. Radiance can also be used to generate annual sun path plots for every hour of the year. This is particularly important in understanding the seasonal and hourly changes of the sun’s position in the sky in relation to building massing, shading and daylight capture.

Figure 2: Radiation Sky Dome and Annual Sunpath

Studies such as the annual radiation analysis shown in figure 3 constitute cumulative analyses. These are particularly relevant at the concept design stage when we are considering annual, seasonal and monthly patterns.

The real power in CBDM comes with a time-series analysis. This analysis uses all of the hourly values

within the climate dataset to predict measurements such as illuminance and irradiance. Time-series analyses are used to assess the daylight potential of a space and considers material properties (transmissivity and reflectivity) as well as building geometric arrangement.

“The real power in CBDM comes with a time-series analysis”.

Figure 3: Cumulative Analysis of Annual Radiation for test building

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CLIMATE-BASED DAYLIGHT MODELLING Parametric design tools such as Grasshopper and environmental analysis plugins Ladybug and Honeybee (http://www.grasshopper3d. com/group/ladybug) have opened up a huge potential in time-series analysis.

These tools allow the user to adapt and amend the design to achieve desired target daylight levels by running multiple design iterations on geometry and material properties.

When considering our simple test building in Birmingham, UK we are able to amend the glass transmissivity values, introduce shading arrangements, amend the window to wall ratio (WWR) and return values in key daylight metrics including, but not limited to, Daylight Autonomy, Useful DayIight Illuminance, and Spatial Daylight Autonomy.

Daylight Autonomy (DA): A temporal metric that describes the annual daylight accessibility.

It is defined as the percentage of total occupied hours that exceeds a specified illuminance level (generally 300 lux is required for an office) Useful Daylight Illuminance (UDI): A temporal metric that describes the potential for daylight comfort. This metric is calculated as same way as Daylight Autonomy, but with difference minimum threshold 100 lux, and a maximum threshold 2000 lux.

As we move into this parametric environment, it is quickly evident that there are potentially thousands of iterations. A relatively simple sounding analysis can quickly build up into numerous studies and more significantly numerous computational hours. For example, if you have 100 nodes in a 1m x 1m grid and 8,760 hours, you now have 876,000 data points. If you run three room depths, three room heights, eight orientations, three WWR’s, and three shade designs, you now have 648 possible combinations, or 567,648,000 data points. If you are looking at DA, UDI,

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and cDA, you now have over 1 billion pieces of data. As mentioned, one issue is the amount of time needed to run multiple simulations for intensive ray-tracing calculations, but secondly there is the issue in presenting data when there are thousands of iterations.

A tool that is able to present this information when exploring multidimensional parametric studies is the Thornton Tomasetti-developed DesignExplorer http://core. thorntontomasetti.com/designexplorer-announcement/. This tool allows the user to navigate through

Spatial Daylight Autonomy (sDA): A spatial metric that describes the percentage of the studied floor area that receives daylight over the target level.’ This metric is calculated based on the results of the Daylight Autonomy study and measures the percentage of an analysis area that exceeds a specified illuminance level (300 lux) for at least 50% of 3,650 annual hours (8am-6pm).

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CLIMATE-BASED DAYLIGHT MODELLING the data and compare different design options and separate those designs that achieve desired target levels.

An additional benefit to parametric environmental design modelling is that

energy modelling can be automated at the same time as the daylight modelling. As changes are made to glazing specification (i.e. TVis and g values) in the same user environment, energy models can be simulated

to return values on cooling and heating demand in addition to other energy metrics. As well as energy modelling, the comfort analysis can be simulated on the same parametric model at the same time. This whole building environmental analysis enables us to consider the impacts on daylight, energy and comfort in one environment and visualise them through tools such as DesignExplorer.

for design teams to establish a framework of simulation that goes beyond revealing, for example, that increased WWR values will allow more daylight into a space. At the same time the ability to interrogate multiple geometric arrangements with design specifications that return valuable daylight metrics gives the design team a far more powerful environment in which to develop an optimised space.

It is important that designers develop a strategy for multiple iteration modelling. Too often in the industry we find that the potential of current software solutions to produce thousands of iterations can cloud the obvious solution. Fifty hours of computational simulation can reveal exactly what the design team knew about the design beforehand with minimal benefit. Before any simulation is developed, it is necessary

While this introduction gives a brief overview of the benefits and potential of Climate-Based Daylight Modelling and parametric modelling, it is only the tip of the iceberg. There is a vibrant buzz around the daylight modelling community with clients and design teams recognising the immense capabilities that we now have available to us.

DCox@ThorntonTomasetti.com

Sources http://climate-based-daylighting.com/doku.php?id=academic:climate-based-daylight-modelling http://climate-based-daylighting.com/lib/exe/fetch.php?media=academic:mardaljevic_cibse_paper.pdf https://www.radiance-online.org/ http://www.lcis.com.tw/paper_store/paper_store/DynamicDaylightPerformanceMetricsInLeukos-20154615155640.pdf http://www.grasshopper3d.com/group/ladybug

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LIGHT TRANSMITTANCE & DESIGN MODELLING

Shedding new light on building energy design requirements John Godley of Hambleside Danelaw discusses the need to use the most accurate light transmittance data available and the consequences of using unreliable values derived from obsolete and inappropriate methods.

With the growing use of more sophisticated energy modelling systems such as IES, owners and specifiers are now recognising the importance of natural daylighting through use of rooflights.

This can make a major contribution to the overall energy performance of buildings, and yet outdated and inaccurate data using obsolete test methods can put this at serious risk.

Most would never dream of using inaccurate thermal performance information or non-fragility claims, so why accept unsafe data relating to this hugely important aspect of roofing design?

Developments in building design have produced a better understanding of the role that rooflights play, but when it comes to specifying them for industrial buildings, many designers still use the outdated ‘rule of thumb’ 10% floor area to determine the number required.

Rooflight manufacturers now need to meet high standards in relation to both non-fragility and thermal performance.

This has resulted in heavier weight products and use of additional layers, both of which can have a significant impact on light transmission.

Building Regulations revisions in

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2006 required a reduction in overall rooflight areas as this was erroneously believed to be right for energyefficient buildings. This, however, ignored the real benefits that rooflights deliver, not only in terms of accepted health and productivity, but positive solar gains in winter months. More significantly, it also disregarded the adverse impact, both in financial and environmental terms, of the increased use of artificial lighting. This was borne out by a De Montfort University study, commissioned in 2003, which demonstrated that most energyefficient buildings utilise high levels of natural light supplemented by artificial lighting (with fully automated dimmer controls).

“Developments in building design have produced a better understanding of the role that rooflights play, but many designers still use the outdated ‘rule of thumb’ 10% floor area to determine the number required.”

Rooflights now deliver significantly improved thermal performance but added insulant layers can reduce light transmission. In the worst cases, the thermal improvement can be more than offset by the demand for increased artificial lighting. Conventional sodium ‘high bay’ lighting typically has a carbon ‘light to heat’ cost ratio of 4:1, and current feedback from building services engineers suggests that even with modern energy-efficient LED systems, this only improves to 3:1.

Past light transmission test methods such as the light box described in

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LIGHT TRANSMITTANCE & DESIGN MODELLING

BS 4154-1:1985 delivered, at best, simplistic light transmission values and a means of comparing one assembly with another. However, such methods are now effectively obsolete given their degree of accuracy in relation to light transmittance, absorptance and surface reflectance. There are many ways to measure the ‘total’ amount of light passing through a relatively thin sample, but most seriously underestimate losses through surface reflectance.

• direct light transmittance through the layer • light reflectance from the surface • light absorptance by the material itself

Rooflight assemblies, particularly those used in large ‘shed’ type buildings, are too deep to be tested as a complete assembly using any currently available test equipment or British Standard test method. To complicate matters, there is inconsistency across different Standards.

Critically, light energy that is absorbed by the material increases in the material temperature, which in turn radiates heat energy both inwards and outwards. This radiated energy is referred to as the ‘secondary component’ which is added to the direct heat energy transmittance from the sun in order to derive a total solar transmission or ‘g-value’.

The character and behaviour of light transmission through multi-layered insulated rooflights is complex.

At every layer, there are three fundamental occurrences:

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In any such assembly, the light that passes directly through a layer is partially reflected back by the next layer. Some of this reflected light will then pass directly back through the first layer while some will be absorbed and some re-reflected inwards.

With accurate physical test data, the calculation method described in BS EN 410 can be used to provide the

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LIGHT TRANSMITTANCE & DESIGN MODELLING best assessment possible of a rooflight assembly’s actual performance.

Understanding reflectance and absorptance is important because: 1. the more layers, the more reflectance; 2. the more material mass contained, the more the absorbance & re-radiation So, as we look for low U-value rooflights, the resulting reduced light transmission can be seriously counterproductive and cause the overall building envelope performance to fall short of the optimum.

So why does this all matter now?

We are building larger industrial metal ‘sheds’ for manufacturing, storage and distribution than ever before.

The energy costs of these buildings, and the impact on the environment has therefore become increasingly important. Generally, the higher the specification of the building, the sharper the focus on thermally efficient rooflights.

Specifiers have a duty of care to use the most accurate data available when designing the fabric and energy performance of a building. Overstating light transmittance values, through unsuitable testing or to obtain a commercial advantage, carries potentially serious implications. Some companies report light transmission values that are up to 10% higher than is realistically achievable. If such data is then used in design modelling, the result will be lights burning brighter and longer when daylight quality is unable to realise what modelling predicted.

between natural light and solar heat energy transmission through rooflights. You cannot simply specify a product with high light and low solar transmission characteristics. When considering the risk of solar overheating, as required by Approved Document L2, overstating light transmission and g-value will lead to under-estimation of the required rooflight area, causing a reduction in light and benefit from solar gain. Any reduction in area can also have the unintended consequence of creating irregular and non-uniform lighting patterns. This can cause shadows and increased potential for glare while the poor light distribution will also be adversely affected further compromised by internal finishes, fixtures and contents.

There are several key considerations when specifying high performance rooflights for the metal building envelope: • type of daylight required – direct or diffused • light transmission level required • total solar gain or g-value.

• uniformity of daylight distribution • area required for adequate lighting • thermal performance

And the cost of getting daylighting wrong?

For building owners and operators these have a huge impact on the cost of running a building throughout its design life. That’s why they put so much emphasis on testing and proving the performance of every element within their asset. A poorly designed daylighting plan can waste money and energy while increasing CO2 emissions, so don’t allow inadequate test data to be the reason for such poor performance. Simple insistence on production of detailed physical test data is all that’s necessary.

There is always a close relationship

www.hambleside-danelaw.co.uk

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“Specifiers have a duty of care to use the most accurate data available when designing the fabric and energy performance of a building.”

www.daylightingmag.co.uk

SPECIAL FEATURE

daylight diary The National Association of Rooflight Manufacturers is reaching out to a wider audience...

May/Jun

e

There was a time when the question “have you heard of NARM,” was invariably answered “No”.

However recently, more and more people in our industry are saying they know about us and our work, thanks to the efforts of our growing band of members and our marketing team.

Greater awareness gives us greater strength to make a bigger difference for our members and for the cause of daylighting in general - so this is great news.

Our website hits are increasing, We’re gaining new followers on social media and more contacts through our membership of the NFRC and the RIBA CPD Provider Network as well as other industry associations.

Our Rooflighting CPD Seminar is now available on YouTube Last year, we produced an on-line CPD Seminar entitled ‘An Indroduction to Daylighting with Rooflights’.

As RIBA-accredited material this seminar counts for double CPD points for RIBA members.

Now, it has been made available to anyone who wishes to access it, irrespective of RIBA membership, on our new NARM YouTube Channel.

www.daylightingmag.co.uk

The Seminar lasts approximately 30 minutes and is relevant to stages 0, 1 and 2 of the RIBA Plan of Work. It is applicable to domestic and nondomestic projects and has been prepared to help specifiers understand the basics of designing daylight into buildings with rooflights

2017

Topics covered include: how rooflights can help to achieve the required light levels for specific building usage and the significant role that rooflights can play in reducing energy usage and CO2 emissions. Knowledge gained from this can be used to inform rooflight design and specification across all sectors.

There are further detailed sections outlining the benefits of daylight to the health and wellbeing of building occupants as well as a guide to rooflight types and glazing materials.

View our CPD Seminar on YouTube Download NARM Technical Documents at www.narm.org.uk Are you a RIBA member?

Book our CPD Seminar now for double points Become a NARM member

May/Jun 2017

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GLASS ROOFLIGHTS

Prestigious Red Dot Award for LED-assisted rooflight LAMILUX world-first impresses international jury

LAMILUX, the leading European manufacturer of rooflights, glass roofs and building control systems, has received a coveted Red Dot Product Design Award for an innovative new flat roof window, that perfectly combines natural and artificial light.

This year, the jury of 41 members assessed 5,200 products for the award. Only those offering outstanding performance, including the LAMILUX CI System Prism LED have received the award.

The new system ensures a high level of illumination and efficiency, with LED lighting integrated into the upstand all around the upper section. The LED modules are controlled by a dimmer linked to daylight sensors. As darkness falls, daylight is gradually replaced with either warm white (2,700K) or neutral white (4,000K) LEDs, to maintain a constant light level, with the optimal combination of daylight and artificial light for maximum energy efficiency.

LAMILUX developed the system

together with the internationallyrenowned light specialists Bartenbach GmbH. Another important feature of the design is a highly reflective finish to the internal surfaces of the upstand.

This allows the LAMILUX CI System to let more natural light into the room, than comparable rooflights with the same opening size. Efficiency during daylight hours is increased by up to 50 per cent, without having to adjust the energy input. Due to the reflector material, rooms can be illuminated for up to 25% longer per day, without the LED lighting being activated.

The origins of the Red Dot Design Award date back to 1955. The institution behind the competition is the Design Zentrum NRW, which has been led by Professor Dr. Peter Zec since 1991. Its distinction, the Red Dot, is established internationally as one of the most sought-after quality marks for excellent design. www.lamilux.co.uk

These photographs show a comparison between daytime daylight levels using standard white internal upstand surfaces (left) and the highly reflective internal surfaces of the LAMILUX CI System rooflights.

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NEW LED-assisted rooflights: a world first for LAMILUX

LAMILUX CI System Rooflights combine energy efficiency with consistent light levels

New LAMILUX CI System rooflights bring new levels of efficiency and round-theclock consistency of internal light levels.

• Upstands incorporate daylight-responsive, energy-efficient sensor-controlled LED lighting • Upstands also feature highly reflective internal surfaces increase light yield during daylight hours by up to 50% • Overall energy savings up to 33% compared to conventional rooflights

Lamilux U.K. Limited (formerly Daylight & Ventilation Solutions Ltd. www.lamilux.co.uk or call us on 01284 749051

GLASS ROOFLIGHTS

Flat Glass Rooflights: A Versatile and Effective Daylighting Solution

By Michael Clark of Roofglaze

“While flat glass rooflights are proven as a cost-effective way to add more daylight and value to domestic properties, they are also now being specified much more regularly on commercial and educational buildings.�

Flat glass rooflights combine the simplicity and convenience of modular rooflights, with the style, practicality and improved light transmission of glass. We have seen first-hand the growing demand for these types of rooflights in recent years.

While flat glass rooflights are proven as a cost-effective way to add more daylight and value to domestic properties, they are also now being specified much more regularly on commercial and educational buildings.

Some of the key factors behind this trend will be examined here.

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Flat glass rooflights provide healthier and more functional internal environments Education Research has demonstrated a clear correlation between classrooms with increased natural light ingress and improved student performance.

Children are able to concentrate better in natural light, so they are more focused and less easily distracted.

Daylight promotes a sense of wellbeing amongst building occupants and flat glass rooflights achieve this without

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GLASS ROOFLIGHTS the potential distractions created by views through vertical windows.

Where vertical windows are not installed, flat glass rooflights provide occupants with beneficial natural daylight contact. Studies also suggest that health is enhanced, helping to improve attendance. Further information about suggested lighting design for schools can be found in the Government’s Building Bulletin 90.

Healthcare In the UK we are used to hearing about Seasonal Affective Disorder, or SAD as it is often referred to. This is a clinically diagnosed condition where the lack of sunlight in winter makes people feel unwell. Natural light helps people to feel better and can also aid the healing process. In hospitals, research studies have proven that the recovery rate of patients is notably accelerated where levels of natural light are increased.

Commercial

Leisure People like bright, naturally-lit environments, which is evidenced by the popularity of domestic conservatories and sunrooms. It is therefore logical that, in their leisure time, people prefer facilities that enjoy high levels of natural daylight. Sporting and recreational facilities will always try to maximise their natural daylight levels in recognition of this fact.

Flat glass rooflights save energy and reduce carbon emissions One of the key reasons for including flat glass rooflights is to provide a bright, naturally-lit interior and reduce the requirement for artificial lighting.

Daylight has many advantages over artificial light; not least the fact that it is a free and unlimited natural resource.

While artificial light is essential, it uses a lot of energy. Reducing its requirement dramatically lowers energy use, and the CO2 emissions resulting from this.

There is a growing body of evidence to suggest that office buildings enjoying higher levels of natural light are more successful than those more reliant on artificial light. In all environments, eye and brain functions respond better to natural light, so people will ultimately perform better. Daylight improves concentration, leading to increased productivity in factories and offices.

Why flat glass rooflights are so often the ideal solution

Studies of retail environments suggest that, in the vast majority of cases, sales are higher in naturally-lit locations. Colours are vivid and true, making goods appear more attractive, encouraging customers to spend more time and money in these stores.

Leading retail organisations now make sure to specify the best daylighting solutions for their store projects.

Naturally, when a large area glazing system is needed then an alternative solution will have to be used, but Roofglaze will always recommend flat glass rooflights whenever it’s feasible to do so.

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“When a costeffective and aestheticallypleasing daylighting solution is required, it is difficult to match the value offered by flat glass rooflights.”

When a cost-effective and aesthetically-pleasing daylighting solution is required, it is difficult to match the value offered by flat glass rooflights. These benefits are just as important to people at home, as they are in the office or the classroom.

www.roofglaze.co.uk

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The Purist Approach Specifying a roof window is a one-time decision for the envelope of a building.

When it comes to choosing one that is in-keeping with the architecture, no other roof window fits the bill quite like ours.

The original and most authentic Conservation Rooflight ÂŽ.

Because modern alternatives just don’t look right.

Find out more 01993 833108 www.therooflightcompany.co.uk

Rooflight dimensions 1070mm x 1870mm

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GLASS ROOFLIGHTS – advertorial

VELUX® ahead of the curve with launch of new rooflights Leading roof window manufacturer VELUX® has launched the world’s first curved glass rooflight for flat roofs.

The VELUX curved glass rooflight features CurveTech, an innovative curve-shaped glass top that lets rainwater easily drain off the surface – even on completely flat roofs.

That means daylight is able to shine through without raindrops getting in the way.

The new curved glass rooflight offers a number of other unique benefits for homeowners looking to bring in more daylight through the roof: A fully programmable control pad offers remote control operation of out-of-reach rooflights. Practical prefitted rain sensor closes the rooflight automatically in the event of rain.

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A combination of insulating PVC frame and double-glazed, low-energy inner pane ensures heat does not escape through the window and helps to maintain the home’s ideal indoor climate.

The curved glass shape provides natural drainage of rainwater, negating the need for regular cleaning.

Toughened glass makes it virtually impervious to damage from the elements. Maintenance free PVC material used on the interior frame is also easy to clean.

Five different sizes of rooflight were made available in April, along with another three at the end of May,

www.daylightingmag.co.uk

GLASS ROOFLIGHTS – advertorial providing homeowners with flexibility when looking for roof windows to match room size.

Recent research into the flat roof window market by VELUX revealed that over half of single storey extensions in the UK have flat roofs, and over two thirds of flat roof extensions have no glazing in the roof.

Grant Sneddon, product manager at VELUX said: “We are extremely proud of our new curved glass rooflight range - the first of its kind in the world.

“Our own research has shown that many homeowners do not realise the daylight potential of glazing in the roof until after they have they have completed their projects With

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our new curved glass rooflight, we have expanded the choice of flat roof windows available to homeowners, allowing them to mix and match to suit each room in their home. Flat roof extensions can often be seen from other levels of the house so, as well as proving a range of interior benefits, we have designed the curved glass rooflight to look great both inside and out.”

“The curved glass shape provides natural drainage of rainwater, negating the need for regular cleaning. ”

The base unit of the VELUX curved glass rooflight is the same as other flat roof window products, making installation hassle free for installers.

The new curved glass rooflight is available now. For more information visit www.velux.co.uk/curvedglass

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COMPANY PROFILE

Filon celebrates 60 years of GRP innovation 2017 is Filon Products’ 60th Anniversary and the company remains a pioneer in GRP rooflights and building products. Sales Director Mark Wilcox takes a look back in time – and discusses the company’s plans for the next 60 years.

Filon Products has been manufacturing high quality GRP sheets in the Midlands since 1957.

Filon was among the first to recognise the outstanding properies of translucent GRP sheeting as a material for rooflighting and enjoyed rapid growth in the late 1950s and early 1960s following the launch of its profiled GRP rooflights for use in the industrial, commercial and agricultural sectors.

The company developed profiled translucent GRP sheets to match the roofing profiles which had become widely used for roofing and cladding factories, agricultural buildings and warehouses. These provided durable and cost-effective ways to introduce daylight into these buildings.

In the intervening years, GRP has remained the most widely specified glazing material for profiled rooflights – and Filon remains a leader in this field, constantly updating its products and developing new innovations to meet the evolving demands of modern construction methods as referenced in The Building Regulations.

Early innovations After the company’s initial successes with its profiled sheet range it explored

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new uses for GRP, including garage doors; internal linings for aeroplanes; specialist products for the North Sea oil industry; solar panels; hoardings; canal linings; traffic signs and other uses. Even today, while the company’s core business remains in rooflights and roof sheets, Filon continues to supply GRP products for a range of other applications, including its Filon mpGRP sheets for safer road signs.

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COMPANY PROFILE

Exploiting the outstanding properties of GRP for rooflighting Excellent light diffusion, high strength and durability are the key factors that make GRP such a suitable material for rooflights. However, this is an over simplification. There are many other factors which need to be taken into account in the design and installation of rooflights and it’s in addressing these factors, that Filon has established its reputation as a true innovator.

Accurate profile matching – the Filon way The Filon GRP production process for example, utilises a unique method of laying the fibres and resin to create accurate profile matches. Accurate profile matching means a better sealing interface between the rooflight and surrounding roof sheets. This becomes more critical as sheet thickness

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increases. It’s for this reason that Filon’s DR and Supasafe double and triple reinforced rooflights have proved so popular. Even with the additional reinforcing layers, the Filon process allows close profile matching, resulting in better sealing and therefore less risk of water ingress.

Jarrow Shipyard in the early 1960s. Rooflights by Filon Products

No-compromise non-fragility Introduced as early as 1992, Filon’s Supasafe triple-reinforced rooflights remain a market leader in non-fragile rooflights. They have been assessed in accordance with ACR(M)001 ‘Test for Fragility of Roofing Assemblies.

Under this classification, they achieve a Class B Non-Fragility rating providing comparable impact resistance and load bearing capabilities to 0.7mm steel sheet.

Filon - the roof safety pioneer Filon has worked in close partnership

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COMPANY PROFILE

with the ACR, the Advisory Committee for Roofsafety, for many years.

Following on from its development of Supasafe rooflights, in 2009 the company introduced Fixsafe.

This unique safety fixing system allows rooflights and roofsheets to be replaced from underneath – eliminating the need for roofers to access fragile roofs. This innovation is a preferred method of the HSE and is now the preferred fixing method of may leading roofing contractors.

Pioneering sustainable solutions Filon is a founder member of NARM, the National Association of Rooflight Manufacturers and as such plays an active role in the association’s long-standing campaign to promote the energy efficiency benefits of daylighting. Filon offers a range of high performance insulated rooflights including its well-known FAIRs (Factory Assembled Insulating Rooflights) which achive U values as low as 0.9 W/m2K. Harsh industrial environments

developed specialist GRP formulations and coatings to provide extended working life in particularly harsh industrial environments such as chemical refineries, tanneries and galvanising plants, where the sheets may be exposed to highly corrosive materials. Filon’s Citadel range has been specifically developed for these applications.

Above left: Filon Supasafe GRP rooflights Above right: Filon Fixsafe in action.

The future is bright...

Filon Sales Director Mark Wilcox said: “Manufacturing rooflights is a good place to be right now, with growing global understanding of the benefits of natural daylight – and pressure on businesses and individuals to reduce energy consumption. At Filon, we remain 100% committed to our core business of rooflights and roof sheets and we will continue our policy of innovation through investment in R&D and production improvements.”

www.filon.co.uk

With its focus on industrial and agricultural buildings, Filon has

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Innovative upgrade & refurbishment solutions for profiled fibre cement or metal roofs & cladding

Upgrade your rooflights and reduce your operating costs by up to

33%

Filon FAIR Factory Assembled Insulating Rooflight

Recent independent research by Elmhust Energy*, demonstrates that improvements to rooflights and lighting controls can bring huge savings in energy and emissions.

In one typical example, a large retail DIY store, total carbon emissions could be reduced by 29% and total operating costs could be reduced by 33%.

These savings equate to a reduction in total operating costs of £5.20/m2 per year, giving a total saving of £20,435 per year.

As one of the UK’s leading providers of profiled rooflights and roofing sheets, with huge experience across all kinds of public and private sector buildings, Filon Products is your ideal partner in roof and rooflight upgrades and refurbishment.

We also offer: • Fixsafe for safe replacement of rooflights and roof sheets • Lightweight over-roofing for cost-effective roof refurb with minimal disruption.

For details, please call us on 01543 687300 or visit www.filon.co.uk

*See the report at http://www.narm.org.uk/ uploads/pdfs/NARM_NTD10.pdf

Filon Products Ltd, Unit 3 Ring Road, Zone 2, Burntwood Business Park, Burntwood, Staffs WS7 3JQ

DAYLIGHT & NEIGHBOURLY MATTERS

Planning for Success: Daylight & Sunlight Amenity Studies In issue 3 Dan Tapscott, head of Neighbourly Matters at Rapleys LLP, summarised the differences between Daylight & Sunlight Amenity and Rights to Light. In this article Dan goes into further detail behind carrying out a Daylight & Sunlight Amenity Study.

By way of a recap, Daylight & Sunlight Amenity considers the amount of natural light a development, the surrounding area and its neighbours are likely to receive following construction of a proposal.

It looks at the amount of direct light (sunlight) and the light from the sky received in all directions (daylight) associated with a proposal. It is purely a Planning matter with the final decision as to what is acceptable being given by Local Authorities.

Guidance on individual Local Authority requirements should be contained within their Local Development Plans and this is always the best starting point for designing a building envelope. Thereafter it is important to review the site and the surrounding areas. Are there any neighbouring building uses which may be particularly sensitive to the levels of natural light they receive? Neighbouring residential properties tend to be regarded as most sensitive but we have looked at schools, hospitals, libraries and some offices before.

There may also be external amenity areas such as parks or playgrounds which will also need to be taken into account. If the arrangement of the development site is unusual and there are lots of surrounding structures then consideration of the arrangement of the habitable rooms in the proposal itself will be necessary.

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The most commonly accepted set of industry guidelines on this subject is BRE Report 209: Site Layout Planning for Daylight and Sunlight – A Guide to Good Practice (2nd Edition) which sets out a sequence of steps to review the situation.

Usefully this contains a preliminary test which avoids having to immediately compile 3D computer models and apply specialist software. The preliminary test involves drawing a section through the neighbouring property and the proposed development, with a 25 degree line from the centre of the lowest

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DAYLIGHT & NEIGHBOURLY MATTERS level window of a neighbouring property. If the line subtends the new development then a more detailed check will be needed to calculate the impact.

If a more detailed analysis is warranted then a 3D model of the development site and the surrounding areas will be required. Rapleys always recommend using a laser scan to obtain a ‘point cloud’ which is then traced around to compile an accurate model. We then incorporate room layouts obtained through data gathering, often in planning archives, and outline the approach taken and sources of information within our report. It still comes as a surprise when we critique reports compiled by others to find that some consultants still use brick counting and guess work, which are unlikely to paint a sufficiently accurate picture.

After incorporating details of the proposal into the model, specialist software is then applied. Rapleys utilise a firm called MBS who supply the software that is arguably recognised as market leading (but a small number of other providers are available). The software produces data spreadsheets and contour drawings which are then scrutinised, considered and presented within the report.

The report, or study, should be factual.

Although the BRE guidance does recommend exercising a degree of flexibility when interpreting the results. Often it is the context of the environment, room usage and nature of the occupiers which are key factors.

City centre locations, configuration of the rooms, transient occupiers within hotels or layouts of study bedrooms in student accommodation schemes are common discussion points.

When we are involved in large schemes with multiple storeys of

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accommodation to review, thought as to how the data is presented always pays dividends. Too much data can make a report seem meaningless, too little won’t give sufficient weight to the conclusions. Sometimes summary tables are good for a quick overview and statistical analysis, especially when dealing with schemes with lots of neighbouring properties. The use of colour to highlight certain things can make life easier for the reader.

Simple inclusions such as a photograph next to the commentary and an identification drawing at the start of the report can go a long way.

“Simple inclusions such as a photograph next to the commentary and an identification drawing at the start of the report can go a long way.”

A common problem we see is a catch all approach having been adopted where erroneous rooms have been included (which may have a bearing for a Rights to Light analysis but not for Daylight & Sunlight). Rooms such as bathrooms, circulation space and storage areas do not need assessing.

It is important just to include what is relevant.

It is worth remembering that Daylight & Sunlight Amenity is just one of many components to a planning application that the local authority must consider in order to reach a balanced decision. However, if the results are pretty damming then all is not lost; it is possible to reverse engineer the design of the envelope to produce an alternative design. Or, as many of our clients do, carry out an envelope study in the first instance, develop the design then run an analysis on a finalised design. The Daylight & Sunlight Study itself can then be brief, confirming all is satisfactory.

Look out for Dan’s article in our next issue where he will be discussing the technicalities behind carrying out a Rights to Light Analysis. dan.tapscott@rapleys.com

www.daylightingmag.co.uk

BUILDING INFORMATION MODELLING

Rooflights & BIM: the way forward Over recent years, the UK Construction industry has moved forward with Building Information Modelling (BIM), quickly making it an everyday tool for the efficient specification of building products. The requirement for BIM Level 2 compliance was a year old in April and now, Chris Lister, General Manager with rooflight Manufacturer JET Cox, looks at how BIM is benefitting the rooflighting industry.

“54% of architects are now using BIM regularly on their projects”

Since its introduction, BIM has transformed construction methods worldwide for those using it and is set to provide unrivalled opportunities to further streamline the relationships between design teams, contractors and clients. It also offers reduced costs via tighter control and increased efficiency.

JET Cox has been manufacturing roofing daylight and ventilation systems since 1954, and fully understands the need to embrace

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change in an ever-developing landscape.

It’s a fact that all technology is moving forward at a substantial rate – and it’s important that we as building product manufacturers keep up. It’s reported that 54% of architects are now using BIM regularly on their projects, with positivity towards the concept continuing to grow, and three quarters believing that BIM will be dominant in the future of project information*.

A statistic we can’t afford to ignore.

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BUILDING INFORMATION MODELLING The technology to facilitate BIM is well established, however the industry’s capability to create and utilise models to their full potential is still in its infancy.

Despite the 2016 deadline, production of BIM objects by the manufacturing industry is still relatively low. Those manufacturers who have invested are starting to see uptake by progressive practices and sole practitioners alike, but for the majority of the construction industry BIM is still a misnomer, known to have importance but still on the ‘to do’ list.

The development of specific modelling packages such as REVIT, alongside the established CAD and 3D modelling suites continues, however, use of these packages requires a change in mindset and technique from architects, engineers and technicians producing them. Furthermore, manufacturers need to understand the modeller’s requirements, to best provide the building blocks for their projects.

In order to assist with this communication, the government coordinated BIM Task Group has been directing input from bodies such as the Construction Products Association (CPA) and The Chartered Institute of Building Engineers (CIBSE) in developing a common language.

This will ultimately take the form of a software package called LexiCon, drawing on all information formats in current use including National Building Specifications (NBS) and Construction Operations Building Information Exchange (COBie) formats.

As with all advances in technology, the pace of development typically produces some disharmony with the range of applications, exceeding the frameworks for control. BIM is no exception. Whilst BIM appears to be settling with REVIT as the standard, supplemented with IFC files, the

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development underway on the language and definition of information contained within the objects is incomplete. Work by the central bodies to define and regulate universal terms is behind schedule and whilst a common data environment exists, the proposed LexiCon software is still unavailable 12 months after the BIM level 2 compliance date.

As a consequence of this, the appointment of Relevant Authorities, the discipline specific bodies from industry being set up to moderate data sets, has been delayed. Whilst this has not stopped the creation and use of BIM objects by the industry, it does bring into question the ability of the Relevant Authorities to ultimately invigilate over the object data template production process.

“The prevalence of UK based architects in the international building design arena has already seen UK manufactured products being incorporated into new BIM designs around the world.”

In the case of rooflights and daylit ventilation systems, the Relevant Authority is the National Association of Rooflight Manufacturers. NARM’s position, as a body containing over 90% of the UK’s rooflight product manufacturers, is central to the production of rooflight BIM objects and their use going forward. With collaborative work already underway to scope out data templates for new objects, NARM is awaiting the launch of the LexiCon software to complete its work. This will allow all manufacturers to use the standardised framework to produce or further develop their existing objects for use in new Building Information Models.

The prevalence of UK based architects in the international building design arena has already seen UK manufactured products being incorporated into new BIM designs around the world. This stems from individual manufacturers’ foresight and readiness, allowing UK designers to use their BIM objects to export UK

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product design around the world. These new tools are a simple extension of product details for specification in a new, all inclusive format.

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Rooflight manufacturers need to continue to make information on their products readily available in the most usable formats and make the specification of their products as simple and as quick as possible.

In addition, the flexibility BIM brings is having a direct impact on the type and frequency of rooflights being specified. As project designs become more adventurous, 360 degree manoeuvrability around the 3D environment is bringing new possibilities for overhead natural daylight. Add to that the ability to easily share model information between project partners, risks can be pinpointed in the early stages thus reducing potentially costly reworking in detailed design, increasing the likelihood of rooflights remaining in completed projects.

In conclusion, the UK building product industry needs to keep capitalizing on new technology to ensure processes are continually improving.

The result will be a well-organised sector, with inclusive systems that offer benefits at every stage of the construction process. BIM is a major part of that and we need to support the advantages it brings to individual companies and UK plc as a whole.

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UNDERSTANDING THE IMPORTANCE OF DAYLIGHT Coxdome Flat Glass is a unique roooight distinguished from other modular units by way of an uninterrupted glass surface, offering pure natural daylight and clear panoramic views internally, whilst providing clean continuous lines on the external roofscape.

From simple one-off installations to the most challenging of residential designs, Coxdome Flat Glass provides the ultimate in roooight technology.

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DAYLIGHTING ICONS The biggest: the best: the most awe-inspiring; the most outrageous; the most influential...

In this regular feature we will be indulging ourselves and our readers with images of daylighting projects throughout the years, that simply deserve a double page feature...

The Menil Collection, Houston, Texas Designed by Renzo Piano in the 1980s, this museum was commissioned to house the art collection of Dominique de Menil, heiress to the Schlumberger oil company fortune and her husband John de Menil.

The museum has only one floor of galleries, having been designed by Piano to complement the scale, orientation and layout of the residential neighbourhood of which the museum is a part.

The design for the roof addressed the client’s wishes regarding the standard of daylight and internal environment within the galleries. To control the daylight entering the galleries, the design developed into separate ‘beam light trusses’ which were later dubbed as ‘light leaves’. Computer and physical models of the light leaves were developed and their shape considered from a structural and architectural viewpoint. The final design proved to be both visually unifying while providing the correct daylight control.

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DAYLIGHTING ICONS

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TRANSLUCENT PANEL SYSTEMS

Changing daylight Architectural journalist Gideon Sykes examines how translucent panel systems are maximising the benefits of daylighting

Daylighting through the creative use of wall or roof glazing, radically changes building envelope design and the ambience of interiors.

It positively influences people, affects how they behave in their environment, changes their circadian rhythm and improves their well-being.

In schools, for example, it is proved to have has an extraordinary calming effect and marked influence on pupil behaviour and learning.

Interestingly, daylight was ‘rediscovered’ by designers in the early part of the last century and this has resulted in glazing now being an essential component of contemporary architecture. This is in spite of Part L which, taken to extremes, means that no daylight at all should penetrate the building envelope! In other words, simply introducing conventional glass can create problems..

While keeping translucent surfaces clean is one problem, the most critical

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are solar control and energy efficiency.

However, things have changed rapidly both in the way the daylight itself is distributed internally and how its performance and effect have been tamed through the use of translucent materials. The glazing industry has come up with a neat trick or two to save the day.

Insulating daylight In the building industry, it is unusual to enjoy new technology which totally changes design and construction.

This is why aerogel insulated glazing is having such a global impact.

Aerogel, the world’s best and lightest insulating solid, is now widely used by many manufacturers within different translucent cladding and rooflighting systems to increase the U value of the glazing.. Sometimes called “frozen smoke”, hydrophobic aerogel is produced as particles, each of which consists of up to 95% air, contained in a structure with pore sizes less than the

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TRANSLUCENT PANEL SYSTEMS mean free path of air molecules. This severely inhibits heat transfer through the glass or panel.

The reason this new insulation technology is so important is because architects and energy-conscious designers can now maximise large areas of daylighting while reducing energy loss and minimising solar glare. Importantly, it means that well insulated daylighting will reduce energy consumption of heating, airconditioning and artificial lighting.

It means that rooflights can be more energy efficient than their predecessors. Also, when aerogel is introduced inside the panels of translucent cladding and roofing systems a U value of up to 0.28 W/m2K is possible. This is as energy efficient as a solid wall.

Diffusing daylight As we know, there are many problems with using large areas of conventional glass – glare, overheating, insulation, energy loss etc to name a few. This is why many architects have now adopted an innovative system which diffuses daylight and provides a different high performance solution.

Not only does it reduce energy consumption heating and airconditioning but carbon emissions are also reduced. In other words, over the building’s life cycle, the capital costs are offset by substantial savings in energy and the quantifiable improvements for occupants in personal wellbeing and performance.

This change is the development of translucent building systems in polycarbonate and fibreglass which alter the impacting daylight and change it into what is often called ‘museum-quality’ light. This is then diffused evenly across the interior to create a quite different and extremely attractive interior ambience.

glazing is that hot spots together with glare and shadows are eliminated and there is no need for internal blinds and curtains. Running costs are reduced because of the superior insulation together with less reliance on artificial lighting. Designers of sports and leisure facilities been quick to recognise that this creates ideal playing conditions. It means that the traditional ‘black box’ windowless sports halls of yesterday have been transformed. It means that swimming pools too have become safer because glare on the water no longer inhibits the ability of life-guards to see swimmers below the water surface.

The lightness of the diffused panels means erection is less costly and, even with a steel substructure, far less cumbersome than glass. The panels have inherent rigidity and impact resistance, are largely self-cleaning and because, dirt is less obvious that on glass, frequency of maintenance is reduced.

“This new insulation technology is so important is because architects and energy-conscious designers can now maximise large areas of daylighting while reducing energy loss and minimising solar glare. ”

Mixing daylight All this new technology dramatically widens the palette of materials available for designers. It gives them the ability to change easily the ambience and performance of different rooms by mixing traditional clear glazing with enhanced solar protection with diffused lighting through translucent panels. It gives them control over the insulating U value performance as well as aesthetics, life cycle performance and the allimportant running costs.

This is particularly beneficial with the current growth in refurbishment of older properties, when many existing curtain-walls and rooflights are having to be replaced and upgraded with a blend of architectural glazing and translucent building materials. www.structura-uk.com/Kalwall

The big difference to conventional

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GLASS RECYCLING

Raise a glass to glass – & recycling In the USA, September is Glass Recycling Month. Jane Embury, Marketing Director at advanced glazing system supplier Wrightstyle, celebrates the wonders of glass – and suggests that we should also have a glass recycling month in the UK.

As a building material, glass is both ubiquitous and timeless. It’s been with us, in the form of obsidian from volcanoes, since the Stone Age. In the form we know it now, glass has been around since at least 3,000BC when the Egyptians, Syrians and Mesopotamians mastered how to make it.

Since then, the history of glass has been largely about its functional and decorative development - from the beauty of the Portland Vase to the rose windows of Notre Dame cathedral.

But the history of glass is much more than that and has, in a very real sense, helped shape the modern world in which we live.

It was glass beakers that helped to create modern science, creating

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knowledge and cures for diseases, and the microscope and telescope, invented in the 16th century, advanced our understanding both of our world and the cosmos beyond.

Let’s also celebrate the humble window, and not just for keeping the elements out. Glass windows, which became more widespread from the 17th century, made homes lighter and brighter - and, partly as a result, plague was eradicated from most of Europe by the early 18th century.

“The EU average recycling rate for glass packaging hit the 73% mark in 2015. The UK rate was 68%.”

And then, of course, came the light bulb, changing our world completely.

(By the way, recycling one glass bottle saves enough energy to power a 100 watt light bulb for nearly an hour).

As a supplier of advanced glazing systems, Wrightstyle is itself playing a small part in the history of glass

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GLASS RECYCLING

– helping, for example, to develop safer systems to withstand fire or the detonation of a terrorist bomb.

But the company is also aware of its environmental responsibility and does what it can to ensure that, whenever possible, all waste materials from its facilities are recycled. Indeed, the UK now recycles well over 1,500,000 tonnes of glass bottles every year – an annual reduction of some 385,000 tonnes of CO2 emission, equivalent to taking more than 120,000 cars off the road.

Data published in 2015 by the European Container Glass Federation (FEVE) found that the EU28 average recycling rate for glass packaging hit the 73% mark for the first time. The UK rate was 68%.

So, although the UK lags behind some European countries, the good news is that waste glass, or cullet, is 100% recyclable, and can be used again and again for a whole variety of glass products. But we can and should be doing more – and that means all of us involved in the building or demolition industries.

Which is why I’m going to raise a glass to glass, and suggest to the powersthat-be that the UK should take a leaf out of the American book and also have a glass recycling month – to help raise awareness of the wonders of this material, and encourage greater responsibility for its disposal by both companies and individuals.

Does anybody out there agree? www.wrightstyle.co.uk

Inspiring Architecture All great architecture starts with a simple idea. Then comes the inspiration to turn it into built reality.

At Wrightstyle we work with architects around the world, bringing to life even the most challenging ideas.

We aren’t just one of the world’s most innovative suppliers of complete and guaranteed steel and glass systems. We’re also world leaders in reinventing what glass and steel facade systems can do.

From large-span or fire-resistant glazing to curtain walling able to withstand a lorry bomb, we are at the forefront of our technologies, pushing the boundaries of what glass and steel are capable of achieving.

Our interior and exterior systems can be found worldwide, and we have a portfolio of examples to illuminate and surprise.

Our systems don’t simply protect buildings against the full range of threats. The inherent strength of steel and our opticallybrilliant glasses allow architects to think in new ways.

So if you’ve got a design idea, talk to us.

We’ll help provide the inspiration to make it happen.

www.daylightingmag.co.uk 17944 Wright Style Advert 210 x 145.indd 1

High Performance Steel & Glass Systems

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Complete & Guaranteed

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@Daylighting_Mag

Twitterings Follow us for regular updates between issues... in the meantime, more highlights...

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DAYLIGHTING MAGAZINE

Stay up to date with DAYLIGHTING Magazine!

Coming up through 2017 – we will be running features on just about every daylighting-related topic you can think of – and some you may not have... We’ll also be offering a wider range of opportunities for advertisers, including low cost product and project feature advertorials, a product finder and an email delivery service, allowing clients access to our email contacts database.

2017 Editorial Programme

NOVEMBER / DECEMBER

REGULAR FEATURES: Industry News & Comment, Technical Focus, Daylight & Energy Saving, Daylighting Standards

• Daylight & Renewable Energy • Daylighting in Factories & Warehouses • Lighting Controls • Translucent Cladding • Roof Windows

JULY / AUGUST • Domestic Daylighting • Controlling Heat & Glare • Daylight in Agriculture & Horticulture • Architectural Glass SEPTEMBER / OCTOBER • Daylight for Dramatic Effect • Daylighting in the Retail Sector • Refurbishment • Modular Rooflights • Daylight Harvesting

Media Information Pack Our Media Information Pack gives details of circulation, advertising rates, 2017 features and editorial policy.

Copies can be downloaded at: www. daylightingmag.co.uk Stay up to date between issues: follow us on social media.

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DAYLIGHTING is published by: Bennett & Partners Pure Offices Lake View House Tournament Fields Warwick CV34 6RG United Kingdom TEL: +44 (0)1295 770833 EDITOR Paul Bennett paul@daylightingmag.co.uk Tel: 01295 770833 Mobile: 07900 895110 AD SALES Miki Bennett adsales@bennettand partners.co.uk Tel: 01295 770833 DESIGN/PRODUCTION Jemma Pentney jemma@bennettand partners.co.uk Tel: 01295 770833 WEBSITE www.daylightingmag.co.uk CIRCULATION Daylighting is available by email, free of charge to subscribers. Our database currently numbers over 6,000 UK architects, specifiers, contractors, consultants and roofing professionals.

Full details are available on our website. www.daylightingmag.com

All rights reserved. No part of this publication may be reproduced or transmitted without the consent of the publisher. While every effort is made to ensure the accuracy of content, the publisher does not accept liability for errors.

The views expressed by contributors are not necessarily those of the editor or publisher.

This publication contains editorial photographs which may have been supplied and paid for by suppliers. Full terms and conditions can be found on our website.

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n D io ts K O W CP uct fligh BO O IBA rod oo N R nt r e n i it h lin A w n- r: g O ina htin m lig Se a y d to

NARM represents suppliers of glass, polycarbonate and GRP rooflight systems for daylighting applications across every sector.

Specifying rooflights?

Look for the logo that means peace-of-mind NARM, the National Association of Rooflight Manufacturers, is the influential trade association representing the UK’s rooflight industry. We are closely involved in developing and implementing legislation affecting UK rooflighting. Choosing rooflights from a NARM member company is the simple and certain way to ensure adherence to standards and legislation. You can also gain access to a wealth of free and objective specification information on our website.

www.narm.org.uk