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Knights Place

Affordable Passive Houses for Exeter by

Exeter

Exeter City Council – Client, Structural and Civil Engineers Gale & Snow den - Architects, Mechanical Engineers and Landscape Architects Jenkins Hansford Partnership – QS

Exeter Office Exeter Bank Chambers 67 High Street Exeter Devon EX4 3DT Tel. 01392 279220 Fax. 01392 279036

Bideford Office 18 Market Place Bideford Devon EX39 2DR (Registered Office) Tel. 01237 474952 Fax. 01237 425669

www.ecodesign.co.uk


Project Design Team • Exeter City Council Project management, Structural and Civil Engineers

Passive Design

Permaculture design

• Gale & Snowden Architects, Engineers, Landscape Architects, Building Physics, Passivhaus consultant • Jenkins Hansford Partnership, QS

Passivhaus certified

Landscape integration


Exeter Infill Sites One of a series of housing projects that Exeter City Council are undertaking as part of their Infill Sites programme

Aims to • Provide affordable housing for Exeter • Raise standards of housing in Exeter.


Merlin Crescent before it was Knights Place


The Project The building design for these 18 flats is based on the Passivhaus methodology and together with Rowan House will be amongst the first multi-residential certified passive houses in the UK. This holistic design strategy allows the units to be operated without a conventional heating system. At the same time, it will avoid overheating in the summer and aims to have a minimal environmental impact. The quality of materials, design and landscaping offers residents a sense of place with a distinctive modern character which they can take pride in over the long term.


Project summary • 18 units • 15 month construction programme • £2.46m development cost • £1.35m in HCA grant funding • Project drivers; – fuel poverty – energy sustainability – future climate change – low maintenance – downsizing – healthy buildings


Key achievements • Building design based on the Passivhaus method will ensure minimal heating requirements and greatly reduced carbon emissions. Knights Place is currently being assessed to become Passivhaus Certified

• Designed to meet future climate change

• Designed to meet Code 4 of the CSH • Fully compliant with Lifetime Homes Standards • All occupants gain private gardens, designed using Permaculture principles

• Solar Panels serving each individual unit will further reduce the energy demand for domestic hot water

• Designed to meet best practice daylight levels in accordance with the requirements of the Code for sustainable homes.

• 100% energy efficient light fittings throughout • Compliant with Secured by Design • Independently assessed under the Building for Life standard with a final score of 18.5 out of 20

• Considerate Constructors Scheme rating of 37.5 out of 40 • Through the use of low water use fittings the water consumption was reduced to less than 80 litres/person/day


What the new tenants think about Rowan House

“We have lived in our 3 bedroom house for 33 years and the thought of moving into a 1 bedroom flat filled us with trepidation.

The flat is so cosy and warm, and the garden feels very rural…the smart meter shows the electricity running at about 0.5 KW per hour. The walk in shower is very safe and we feel safer than climbing out of a bath After only a few weeks we are really happy in our new home”


How does it work? • Compact form • High Levels of insulation and high performance windows and doors • Thermal bridge free • Air-tight envelope

• Highly efficient Mechanical Ventilation Heat Recovery (MVHR)


How does it compare to a standard build ? The holistic design strategy allows for energy savings of up to 90%, making these units truly affordable and protecting future tenants from fuel poverty.


Knights Place Reduced running costs EPC estimated results – heating hot water and lighting Knights Place (flat 5)

Approx UK Standard

units

Energy Use

73

280

(kWh/m2/year)

Carbon Dioxide emissions

0.6

2.5

(tonnes per year)

Lighting

£24

£80

(per year)

Heating

£18

£450-500

(per year)

Hot water

£86

£230

(per year)

On average energy prices in the past 10 years have increased by approximately 10% per annum. With current trends in energy and fossil fuels it is not likely that this will change over the next 10 – 20 years. Assuming a 10% increase per annum, £800 today (typical heating and hot water cost per annum of an existing flat) would be in 5 years time = £1171, in 10 years time £1, 715 The project has recently received funding from TSB to monitor energy and building use.


Healthy Buildings • Non-toxic eg: non VOC materials • High quality ventilation • High levels of natural daylight • Thermal comfort • Avoidance of dust mites by good design and materials selection • User control • Radial wiring to reduce low frequency Electro-Magnetic Fields (EMFs) • Non PVC materials specified


Landscaping Permaculture principles Landscape Architect and Species expert as part of Gale & Snowden in-house design team. Emphasis on integrated design using Permaculture principles Working with natural system not against


Neighbourhood • Considerate contractors

• Liaison over garden design • Shared garden spaces • Use of local apprentices

• Use of local labour • Newsletters • Bringing forward external works to adjacent block


What we’ve learnt • The need for greater contractor collaboration and learning

• Greater consideration on work sequencing and UK weather

• A more unified culture across the delivery team would help

• To simplify the design • Greater lead in time would be beneficial • Repairs and maintenance team early involvement proved valuable

• We would do it again and better


Extra Care 4 Exeter Key Issues • First Passivhaus Care facility in UK • Designed around user needs • Healthy building design • Designed for future climate change adaptation – TSB funded


Future Climate Change Adaptation Overheating Criteria not to exceed 1% occupied hours over 25 oC

Passive cooling

Cross flow vent 10-15% over heating improvement over single sided ventilation

• Cross ventilation • Super insulated envelope • Intelligent Ventilation control • Extracting heat at source • Mass vs light weight • Living plants / landscape • Solar shading

Super-insulated, air tight envelope helps to stabilise internal temperatures and reduce solar gain penetration 3 – 6% improvement

Intelligent window control 4% improvement Mass vs light weight 2-4% improvement with mass Less 1.5oc by microclimate

Local shading 2% improvement

Evaporation / Transpiration

Pleasant shaded spaces for cooling Relocation of internal heat gains from plant outside thermal envelope 5% improvement

Green microclimate reduce summer temperatures by 3oC

Green roof


Life Cycle Costings


Swim 4 Exeter A new indoor public municipal pool facility for Exeter, designed to meet Passivhaus standard including a main National/County standard swimming pool and a learners pool with supporting facilities and fitness area.


Knights Place

Affordable Passive Houses for Exeter by

Exeter

Exeter City Council – Client, Structural and Civil Engineers Gale & Snow den - Architects, Mechanical Engineers and Landscape Architects Jenkins Hansford Partnership – QS

Exeter Office Exeter Bank Chambers 67 High Street Exeter Devon EX4 3DT Tel. 01392 279220 Fax. 01392 279036

Bideford Office 18 Market Place Bideford Devon EX39 2DR (Registered Office) Tel. 01237 474952 Fax. 01237 425669

www.ecodesign.co.uk


Knight's Place Presentation