Fenestration Volume Three

FENESTRATION New Zealand

Autumn 2022

Z ER0

ENERGY

CARBON

WASTE

How New Zealand’s buildings can support our climate goals – starting today!

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FMI ZERO

Zero Carbon houses: fantastical or feasible?

Durability = Sustainability

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Durability, not just performance

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Zero Energy homes still well ahead of the updated code

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Less cold, less mould

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Contents 3

Editor’s Note

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FMI ZERO

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FMI Zero Energy homes still well ahead of the updated code

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FMI Zero Carbon houses: fantastical or feasible?

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Less cold, less mould

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Durability = Sustainability

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Durability, not just performance

Publisher FMI Building Innovation Telephone: +64 9 574 2900 100 Carbine Road, Mt Wellington,1061 2-6 Timaru Place, Mt Wellington,1061 PO Box 51075, Pakuranga, 2140, Auckland, New Zealand 1

One word best describes our Fairview brand

MD Aluminium

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Editor’s Note “FMI Zero”: it’s more than “FMI Zero Energy” Welcome to the third issue of Fenestration New Zealand Another issue of this magazine dedicated to our research into energy and building efficiency, and another New Zealand annual heat record... NIWA reported that 2021 hit an average temperature of 13.560C, surpassing 2016’s prior record. Meanwhile, late last year, MBIE issued a higher standard of energy efficiency for housing and small buildings.

It’s a move in the right direction to rein in climate change by cutting emissions from our building and construction sector – yet the gap to the quality of homes we need to be building still stretches wide.

It needn’t be so. Since our last issue, we’ve been broadening our view of how new-build homes can contribute to significantly lower emissions.

Cutting energy use per square metre and generating renewable energy where possible both matter, but so too does avoiding materials with a high embedded carbon content and transport miles to the house site.

Not wasting material onsite or in refurbishments and repairs during a house’s life also add up.

CORRECTION to Fenestration New Zealand Issue 2 In our item “A model is... just a model” (page 49) we stated that BRANZ had used PHPP to conduct research for the new H1 building code options.

This was incorrect. BRANZ used EnergyPlus v9.2.

We regret the error.

We’re now envisaging a new-build home that meets the zero energy definition, achieves zero carbon through its life by netting off surplus onsite generation, and is delivered with zero waste by reusing, recycling and returning excess building materials to nature.

We call this home “FMI Zero”, built on the three pillars of FMI Zero Energy, FMI Zero Carbon and FMI Zero Waste. FMI Zero is the lens that guides our development efforts towards homes that are energyefficient, zero-emission, healthy and affordable.

Read on to find out how our FMI Zero vision is closer to reality than you may think.

WARREN LEWIS MANAGING DIRECTOR FMI BUILDING INNOVATION

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FMI ZERO

FMI Zero Energy (FMI ZE) An FMI Zero Energy (FMI ZE) home produces as much renewable energy from solar panels on its roof as its occupants consume over the course of a year. It achieves this net zero balance via a highly energy-efficient building envelope combined with the most fit-forpurpose appliances. An FMI Zero Energy Ready home (FMI ZER) is an FMI ZE home without the solar panels.

Depending on technology and local incentives, surplus energy from the roof may be sold to the grid or stored.

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FMI Zero Carbon (FMI ZC) Over its lifetime, an FMI Zero Carbon (FMI ZC) house generates enough surplus renewable energy from its roof to cover not only the operational needs of the occupants but also to offset all the embodied carbon in its construction and ongoing repair and maintenance. The offset also covers embodied carbon in the solar panels and fittings.

Strategies to minimise embodied carbon in the FMI ZC house include initial design, low carbon and durable materials selection, and avoiding construction waste.

FMI Zero Waste (FMI ZW) Embodied carbon is wasted throughout the life cycle that builds, maintains, and eventually dismantles a house. An FMI Zero Waste (FMI ZW) house construction site reduces embodied carbon by sending nothing to landfill. Instead, it • REUSES leftover materials in subsequent construction.

• RECYCLES packaging and leftover materials back to building suppliers, and favours suppliers who can offer this service.

• RETURNS TO NATURE provided materials are non-harmful and organic.

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FMI Zero Energy homes: still well ahead of the updated code A new Code in town The good news, as many of you know, is that MBIE issued an update to the H1 energy efficiency section of New Zealand’s building code, effective from late November 2021. For housing and small buildings, it boosts thermal performance by increasing insulation and glazing quality in new builds.

The consultation process for the update garnered almost 700 submissions for the housing and small buildings section, an unprecedented level of engagement. The Outcome document1 reported “overwhelming support for change” with a key feedback theme that the changes were “long overdue”. At FMI we say the same! Every house we build or retrofit to less ambitious emissions targets than the industry is capable of delivering locks us into suboptimal performance for upward of fifty years of the building’s life. We also agree with comments by Jason Quinn from Sustainable Engineering on the update:

It’s not perfect, it’s too slow, it needs to go further—but it’s the first step in a planned transition to the far better buildings we need to address climate change and improve people’s health and comfort.2 The theme of respondents wanting bigger and quicker changes had also come through in earlier feedback on MBIE’s Building for Climate Change proposals that sought to address operational and embodied emissions in the building sector. In the Summary Report’s3 own words:

There was support for the Framework’s scope to be wider and timeframe more ambitious

A sense of urgency was prominent throughout many responses.

In fact, 55% of respondents wanted the operational efficiency requirements to be implemented ahead of the proposed 2035 timeframe. Many respondents referred to the long planning time frames that construction projects typically run on, meaning positive impacts from any new regulations would have an inherent delay.

For those of us passionate about lifting the efficiency and healthiness of New Zealand homes, the H1 update helps our cause, even if we wish it had gone further and faster. The cost premium to build a better home than mandated by the code is now lower. The premium for our FMI Zero Energy / Ready (FMI ZE/R) home was only 4-6% more than the old Code, but it will now be even less, weakening a common objection to building better.

Encouragingly, the outlook is for the premium to shrink further. The recent update is merely the start of emission reduction changes signalled in Building for Climate Change.

We are finally moving along a track towards affordable, high-performance homes that benefit residents and the environment. The approach to such dwellings can vary, from FMI’s Zero Energy design to the currently better-known Passive House, but they draw off similar tools, concepts, and concerns, many of which have yet to be reflected in the construction guidelines for New Zealand homes.

https://www.building.govt.nz/assets/Uploads/building-code-compliance/building-code-updates/outcome-consultation-building-code-update-2021.pdf https://sustainableengineering.co.nz/analysed-h1-code-changes/ 3 https://www.mbie.govt.nz/dmsdocument/14726-building-for-climate-change-summary-report 1

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More climate zones The update has increased the number of climate zones that impact H1 building code standards from three to six, as shown in Figure A. About 60% of New Zealanders live in Zones 1 and 2. Of our major centres, Auckland is in Zone 1, Wellington in Zone 3, and Christchurch in Zone 5. Queenstown is typically used to model the coldest climate in Zone 6. The aim of more climate zones is to “allow the insulation requirements to better reflect the different temperatures experienced in each zone”.

The zone definitions are not an exact science, however.

For administrative reasons, the proposed zones were bent around territorial authority (TA) boundaries. Two TAs pushed back during consultation, seeking a zone split between their coastal and alpine regions to better achieve the aim of the exercise. BRANZ’s analysis4 of the demands of the six zones on home heating and cooling also identified some cases that were hard to classify, including the country’s fourth and fifth largest centres of Tauranga and Hamilton. Nevertheless, the Outcome document stated that the majority of respondents were in favour of the principle of more finely sliced and diced climate zones.

At FMI we beg to differ, even though we accept we are in the minority. In all FMI’s submissions concerning proposed changes to reduce emissions and enhance residential building quality we have consistently pushed for simplicity. Specifically, we remain in favour of one set of H1 performance measures across the country. We would rather “gild the lily” in warmer zones (noting that the energy savings of FMI’s Zero Energy home produce an attractive NPV regardless of “gilding” in Zone 1) than navigate a regional variety of performance standards with attendant compliance checks.

In our calculations for the previous issue of Fenestration New Zealand, we found our FMI Zero Energy home had an initial build premium of $34,000, almost exactly the $33,000 amount spent on Preliminaries that encompassed design and professional fees, consent fees, development contributions, service connection fees, and essential testing such as Geotech and structural. The more finely MBIE sets standards, the greater the burden on many of these upfront costs.

FIGURE A:

Past versus Newly Adopted Climate Zones

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https://www.building.govt.nz/assets/Uploads/building-code-compliance/background-report-on-h1-energy-efficiency-branz.pdf

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So many permutations Building a house is already a complex undertaking in New Zealand. Beyond H1, many other building standards are already in place, relating both to macro/ regional and micro/ site-specific conditions. Each variable places a demand on the complexity of the design and building processes.

We did a quick reckoning of the many zones and classes that affect broad swathes of the code for timber-built homes. In addition to the now 6 climate zones, we found: • 4 earthquake zones • 3 corrosion zones (actually 4, but 3 and 4 are treated alike)

which would “only” have been 1300 or so if the climate zones had not doubled. This high number is before the many other considerations such as the need to build on good ground, to assess natural hazards like flooding and erosion, to comply with restrictive aspects of the relevant District and Unitary plans etc., etc. Further, the E1 standards around external moisture demand attention to a region’s historical rainfall intensity to assess drainage and guttering needs to cope with surface water as well as adequate weather proofing to keep moisture outside the building envelope. It’s a wonder anyone attempts to build!

Ahem. Time to climb down off our simplicity soapbox and return to a calm review of the H1 update.

• 6 snow load zones • 6 wind zones calculated based on yet more factors: o 2 wind regions including Lee areas o 4 topography classes o 2 ground roughness classes o 2 site exposure types …producing almost 2600 potential permutations –

More insulation Roof insulation requirements have doubled for the coldest climate and more than doubled in the warmest.

Windows, acknowledged as the greatest source of heat loss with current standards and installation methods, have also seen significant increases in required performance. New builds in Queenstown very nearly double in R value for windows, while in Auckland the performance lifts by about 40% in Year 1 and 80% in Year 2 – the staggered approach is to give window manufacturers time to retool. By contrast, much less ambitious changes have been applied to walls and floor slabs.

Prioritising certain envelope components over others makes a lot of sense to us. In our first issue of Fenestration New Zealand we analysed the “bang for buck” of different components for their cost relative to their impact on energy savings. The payback was best for high-performing windows. We are therefore

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not surprised to see window upgrades receiving emphasis in the update. It is less clear to what extent MBIE have prioritised roofing insulation over walls and slabs because it is easy to do, with no effect on framing requirements, versus its cost effectiveness over the other components.

The higher requirements for roofs and windows are broadly in line with respondents’ preferences for significant change. 45% wanted New Zealand’s code to move up to international standards while another 45% wanted it to exceed them. At FMI, perhaps predictably, we wanted to go beyond the ‘beyond’. Generally, however, the new standards drift further away from international standards the colder the climate zone, as shown in Figures B and C.

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FIGURE B:

R values for roofs in homes

FIGURE C:

R values for windows in homes

Several things have not changed with the update to the H1 clause. Output-based measures of energy performance (such as kilowatt hours per square metre) that could link to our national climate change goals are absent, though they may be introduced in a couple of years; for now, we largely remain in the world of specified inputs in the form of R values. Overheating, air tightness, thermal bridging, ventilation, and moisture concerns are acknowledged but not tackled. The core objective of the update is restricted to heating demand, yet this is only one of the three key uses of energy in the home, alongside hot water heating and plug load.

For all the gripes, the new standards will yield some power savings for new-home dwellers and slightly lighten the peak winter and evening loads on our national grid. MBIE reports the changes, when applied to their Energy model of a single storey 4-bedroom house of 150m2, will save about 40% of the electricity needed to heat and cool the home to comfortable levels. The saving is consistent across all the new climate zones. Since, as a rule of thumb, heating demand uses about a third of the energy in a home, a 40% saving in heating demand could cut power bills by 10-15%.

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FMI Zero Energy home remains well ahead How much energy saving upside remains to be captured from better-built homes like FMI’s Zero Energy design?

The short answer is plenty.

Recapping briefly, an FMI Zero Energy home produces as much renewable energy from solar panels on its roof as its occupants consume over the course of a year.

It achieves this net zero balance via a highly energyefficient building envelope combined with the most fit-for-purpose appliances. An FMI Zero Energy Ready home is a FMI Zero Energy home without the solar panels.

Our model home is a detached, single-storey, threebedroom family home of 120m2. Passive design strategies such as optimised window placement have been avoided to keep the house looking typically Kiwi.

Our house has four occupants who seek a temperature range throughout the building and across the year of

FIGURE D:

20-200C and who are frugal with hot water. All the modelling has been done by architectural engineers certified in the use of the Passive House Planning Package (PHPP).

Our FMI Zero Energy build components do not vary by climate zone, reflecting our previously explained preference for simplicity over tailoring. As we continue to learn more, however, we do amend the performance rating of our components and we try out new appliances. Indeed, the latest FMI Zero Energy/ Ready performance values are all reduced from those in the second issue of Fenestration New Zealand.

Key parameters for our latest modelling, reflecting AsDesigned R values, compared to the updated H1 clause in Zones 1, 3 and 6 are as follows in Figure D.

Insulation, glazing and key appliances by climate zone for updated code and FMI Zero Energy/ Ready (FMI ZE/R) builds

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Nothing in our analyses to date has undermined our early insight that the single best investment in lifting building envelope efficiency at least cost is to install very high-performing windows. Unlike MBIE and many of the respondents to the building code consultation, FMI is confident that at least one local manufacturer can produce commercial quantities of such high performing windows…

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Using our model, the shift from the old building code to the updated one saves about 50% of heating demand across all zones except Zone 6 where the saving is, as for MBIE, 40%. Of greater interest to us, however, is how much lower the heating demand in our FMI ZE/R home is than in the updated code. Figure E shows the savings are a staggering extra 66 – 84% depending on climate zone.

What savings, then, does the FMI Zero Energy / Ready house produce in heating demand?

FIGURE E:

Heating demand for old and updated H1 code vs FMI Zero Energy/Ready (FMI ZE/R) build (kWh/m2)

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Are we there yet – Building for Climate Change?

One definition of journey’s end would be to say we are “there” if our FMI Zero Energy home performs at or below the final energy caps set out in Building for Climate Change. The caps are simple and appear to reflect some Passive House standards. No fossil fuels are to be used, and the total electricity use per square meter should not exceed 45 kWh per year. The 45 kWh splits out as: • thermal (or heating) demand:

15 kWh p.a.

• delivered services (hot water, ventilation etc) 15 kWh p.a.

• occupant behaviour (plug loads)

15 kWh p.a.

Any on-site generation of renewable energy paired with storage counts as useful capacity that can be subtracted from the total modelled energy demand to help a home achieve the caps. Our FMI Zero Energy home is designed to generate on-site energy for immediate use – we’re not convinced about storage yet – and may qualify.

As written in August 2020, Building for Climate Change makes no allowance for different climate zones. Whether

in Kaitaia or Bluff, homes are expected to meet the caps.

Figure E may seem to suggest the FMI house will come up short on the heating demand cap in Zone 6. In fact, because of the coefficient of performance (CoP) of 3.0 on the heat pump, the actual heating demand at the electricity meter is only 10 kWh/m2. In Zone 6, the cooling demand, which is not considered in the recent H1 update, is only 2.1, bringing the total space conditioning energy comfortably under the thermal cap.

For completeness, Figure F shows our modelled estimates of total electricity use for a home built to the updated code versus our FMI design. More detail is available in the table in Figure G. In each zone shown, FMI’s Zero Energy home sits below the total cap before any benefit from onsite generation. The total energy saving for the FMI Zero Energy/ Ready versus the updated code house in Zone 6 is almost 50%. It is worth noting the upside of almost 18 kWh per year (26.7 vs 8.9) that the new H1 code house could have achieved with a heat pump hot water system instead of using direct electricity.

FIGURE F:

Electricity by use for updated code vs FMI Zero Energy/Ready (FMI ZE/R) build (kWh per m2)

The key message in Figure F is that our FMI Zero Energy/ Ready homes already meet the proposed final 2035 energy caps, in all climate zones. They do this at what will now be less than the 4–6% cost premium over the old code given the increased spec embodied in the

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update, and the reduced spec for FMI Zero Energy / Ready shown in Figure D. All this is also before deducting power savings from the FMI Zero Energy home’s on-site generation and any income from selling surplus back to the grid during summer.

THE EXPERTS AGREE

Solace -Low-E Provides Greater Insulation, More Comfort and Healthier Homes Solace Low-E is an advanced thermal glass technology that provides year-round energy efciency and comfort. Designed to withstand New Zealand’s harsh climates.

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Are we there yet – Passive House?

An alternative journey’s end, but linked to the above, would be for our FMI Zero Energy / Ready house to perform to Passive House standards. We thought it would be interesting to explore this angle, given the commonality between FMI Zero Energy and Passive House for pursuing high energy efficiency, yet also underlying differences in objectives between the two approaches.

per hour. Our FMI Zero Energy / Ready home, modelled in PHPP9 which allows for building-specific amendments, initially fell short even though it met standards for air changes and for fRSI. However, small tweaks to air changes per hour (increases!) brought Zones 1, 2 and 3 into line with Passive standards, with the proviso that the site be free of shading from trees and other buildings.

FMI Zero Energy is focused on achieving a zero energy balance in the building’s operation, ahead of considerations like occupant health and comfort (which certainly improve in tandem with energy efficiency but are not a primary goal). In our specific FMI Zero Energy home, we had also deliberately tilted the design against meeting Passive House standards because we wanted the building to have a style familiar to many Kiwis. In particular, we kept the windows generous in size and number, where Passive House would have opted for fewer, smaller ones.

The three colder climates failed on heating demand: Passive House requires a maximum of 15 kWh/m2 and does not consider the CoP of the appliances used, nor, in Passive Classic, the building’s capacity to create renewable energy from its roof as an offset.

Interestingly, our house did meet the Low Energy Standard for heating demand in all the cold climates, because all fell under the limit of 30 kWh/m2. For thermal comfort, Zone 6 was the only zone in which our house failed; it would require even better glazing to meet Passive House.

Passive House considers several factors before accrediting a home. These include heating demand, thermal comfort, fRSI (a measure of how uniform internal surface temperatures are, and how close to the internal air temperature) and air changes

We were impressed that our simple Kiwi box, designed to achieve FMI Zero Energy, should have passed in every climate as a Low Energy home and in three as Passive House.

Next steps We believe it is feasible right now to build simple homes that are affordable and materially better for residents and the environment than the updated H1 clause will deliver.

Despite pandemic-related operational pressures, we still fully intend to build a test home in the key Auckland market to prove our convictions. With New Zealand internationally obligated to meet challenging carbon emission reduction goals, we surely need the large

Se

building and construction sector to do what it can, as soon as it can.

And then we can work on efficient ways to retrofit the bulk of existing homes in order to make an even greater contribution…

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Scratch-Resistant Powder Coat Technology

Flaxpod

Light Cherry Dark Cherry

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Ironsand Grey

Light Cedar

White

Grey Friars

Dark Cedar

Arctic White

Charcoal

Light Bean

Black

Monument

Dark Bean

FMI Building Innovation

Sandstone

Dark Riverwood

Black Riverwood

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FIGURE G:

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Modelling outputs for the updated H1 code and for the latest FMI Zero Energy/Ready home

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Z ER0 Designing for a better tomorrow

Next generation windows & doors.

T H E L AT E S T G L A S S S PA C E R T E C H N O LO G Y I N I N S U L AT E D G L A S S U N I T S ( I G U ) LO N G E V I T Y Redefining standards for double glazing spacers around the world, FMI Building Innovation’s XR Edge is a multi-component system certified for all climate zones in New Zealand.

Designed to reduce internal condensation within an insulated glass unit, XR Edge is a revolutionary spacer for greater thermal efficiency and IGU longevity.

W H AT I S A

S PAC E R

A spacer is a component that holds the two panes of glass apart within an IGU. Its main role is preventing moisture passing into the IGU, reducing the possiblity of internal condensation and fogging.

U g yin r pla ce dis spa er GE rn Co R ED X

With carefully manufactured insulating glass panes, our customers can expect the longest IGU life possible. That’s where XR Edge comes in.

IG

Typically, average spacers will often lead to IGUs failing prematurely due to climate and mechanical loads as well as material incompatibilities that cause the spacer sealants to leak.

WHY GO

XR EDGE Made up of five different components, our rigid spacer system has been designed to withstand New Zealand’s climates.

UNBREAKABLE BARRIER

Unlike other spacer manufacturers, we use a stainless steel vapour barrier and combine it with a structural core made of polypropylene that offers a superior thermal performance, and greatly reduces moisture permeability.

TWICE AS MUCH DESICCANT

Although the chances of moisture passing through the stainless steel barrier are little to zero, a desiccant material is used to fill the hollow core of the stainless steel and polypropylene spacer to absorb any moisture within the air cavity.

Our spacer structure allows us to use twice as much desiccant than standard spacers. The more desiccant used, the more moisture can be absorbed, and the longer the unit lasts.

LONGER LASTING IGUS

All four sides of our XR EDGE spacer are filled with desiccant, which in turn allows for maximized IGU performance. Our multi-component spacer system ensures our customers obtain the longest IGU service life possible.

THE FMI

DIFFERENCE Years of international research, rigorous testing, and thermal analysis have allowed us to formulate what we believe to be New Zealand’s greatest in spacer design.

We are proud to be New Zealand’s first glass manufacturer to have an IGU test lab on our own premises.

Our facilities allow us to simulate real time weather climates right here in our own factories to verify our product is fit for purpose.

The outcome? We find better solutions for our products faster, and in turn increase our manufacturing capabilities across our supply chain.

XR EDGE spacer exploded

At FMI Building Innovation we have our fingers on the pulse of industry breakthroughs which allows us to be in charge of our own destiny. We do not compromise on quality for cutting-edge technology and always push the boundaries for the latest in innovation.

THE

BREAKDOWN 5

1. Desiccant: Removes moisture from the enclosed air during production and subsequently absorbs water vapor that penetrates until the end of its absorption capacity.

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2. Primary Sealant (PIB): Maintains gas tightness and minimizes moisture ingress into the unit. PIB is applied to the sidewalls of the spacer and creates a seal between the spacer and the glass.

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3. Secondary Sealant: Provides mechanical stability to the entire IGU and protects the seal from environmental influences.

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XR EDGE spacer

4. Stainless Steel Vapour Barrier: Stops desiccant absorbing moisture from outside of the unit.

5. Warm Edge Box Structure: A composite box structure that gives the entire spacer unit overall strength and a warm edge performance.

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HOW DO WE

CO M PA R E

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3

ALUMINIUM SPACER

FOAM SPACER

THERMOPLASTIC SPACER

RIGID SPACER

P

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WARM EDGE

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DESICCANT ON ALL FOUR SIDES

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P

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50%

35%

35%

100%

ZERO EXTERNAL VAPOUR PERMEATION

P

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STAINLESS STEEL EXTERNAL VAPOUR BARRIER

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FEATURES

DESICCANT MOISTURE ABSORPTION CAPACITY

To find out more about our XR EDGE spacer email: archteam@fmi.co.nz or visit: fmi.co.nz.

FMI Zero Carbon houses: fantastical or feasible?

National carbon goal New Zealand is on a journey to net zero carbon1 by 2050. Reaching this goal, if we do, will be our national contribution to the global effort under the Paris Agreement of maintaining the world’s temperature rise to no more than 1.50C above pre-industrial levels.

Net zero carbon at a country level means achieving a balance between the volume of carbon (carbon dioxide and equivalent greenhouse gases) emitted from activities across industry sectors and society,

and the volume of carbon taken out of the national system either by sequestration in carbon sinks like forests or—as a stopgap—buying carbon credits from another country. Our FMI Zero initiatives contribute in their different ways to reducing the volume of carbon emissions from new houses and commercial buildings, and thus reduce the sinks and credits required.

Definitions Agreeing definitions and measurements is an important part of assessing starting points and charting progress from them. The contribution our local building and construction industry makes to New Zealand’s carbon emissions today ranges widely, depending on three considerations: • Are all three of a building’s emission types included?

Embodied carbon comes from the manufacture and transport of materials that form the building and can occur right across the building’s life cycle. Operational carbon occurs only during the use stage of a building’s life from the energy and other resources like water used to operate the building. Refrigerant carbon in homes typically comes from refrigerator 1 2

Excluding biogenic methane from agriculture and organic waste “Transitioning to a low-emissions and climate-resilient future”, MfE, October 2021

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and air conditioning systems which contain gases far more warming to the atmosphere than carbon dioxide • Where along the chain of building activities is the carbon deemed to be emitted? A production view accounts for emissions at the point they are emitted, such as a factory. A consumption view accounts for emissions in goods and services at the point they are finally used, typically further along the value chain • How have activities in the industry or social sector been allocated? In its consultation document on New Zealand’s Emissions Reduction Plan2, the Ministry for the Environment (MfE) allocated the operational energy to run homes and commercial buildings to

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the Energy & Industry sector rather than to Building & Construction.

Combining a production approach with embodied and refrigerant emissions puts 4%3 of this country’s carbon at the building industry’s door. Expanding to all emission types and a consumption view, the share rises to 20% of this country’s carbon. Globally, the latter number has been estimated at almost 40%4.

It would be fair to say that developing and harmonising measurement approaches to different aspects of carbon emissions is still a work in progress both internationally and nationally. This is certainly true in New Zealand where the wider building industry is new to concepts

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of carbon emission management and measurement. To date these have been familiar to a handful of interested practitioners of high energy efficiency construction with an emphasis on operational rather than embodied carbon emissions.

What do the terms we use in our FMI Zero Carbon initiative mean? The schematic on pages 4-5 steps through our definitions for FMI Zero Energy, FMI Zero Carbon and FMI Zero Waste. FMI Zero Carbon, which we explore in this article, refers to a house designed and built to minimise its lifetime embodied carbon emissions and, further, to fully offset those emissions with renewable energy generated onsite that is surplus to the occupants’ operational demands across the seasons.

Embodied carbon: a life cycle The notion of cradle to grave (and beyond) is core to international thinking on managing embodied carbon out of buildings. This is because, unlike operational carbon which can be reduced during a building’s lifetime, embodied carbon is locked in as soon as a building is constructed.

In the initial years of a building’s life, embodied carbon also represents a significant share of carbon emissions. BRANZ has calculated that in the first thirty years of a newly built detached house’s life, embodied emissions contribute 45%6 of its total emissions; the share falls to a little over a quarter by the end of its ninety-year life – see Figure 1.

FIGURE 1:

The contribution of materials, energy use and water consumption to a new house’s greenhouse gas emissions over 90 and 30 years (source: BRANZ)

Successive life stages of a building have been defined in European standard EN 15978:20117 and adopted by the Ministry of Business, Industry and

Enterprise’s (MBIE) in their Building for Climate Change programme8 as shown in Figure 2.

Ibid Whole-of Life Embodied Carbon Emissions Reduction Framework”, MBIE, August 2020 5 “2018 Global Status Report” for Global Alliance of Building and Construction 6 “A carbon budget for New Zealand houses”, BRANZ Research Now: Zero-carbon built environment #1, September 2020 7 “Introduction to LCA of Buildings”, Danish Transport and Construction Agency, 2016.

8 Whole-of Life Embodied Carbon Emissions Reduction Framework, August 2020 3 4

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FIGURE 2:

Module framework for life cycle assessment of buildings

To date, more attention has been given to the challenge of cutting operational carbon (B6 and B7 in Figure 2) than embodied carbon. The result has been more advanced design and measurement systems for operational carbon, including Passive House standards for energy efficiency and indoor comfort.

As building practices for energy efficiency improve and are used more widely, and as renewable energy powers a greater proportion of building operations,

however, the prize for reducing operational carbon will likely fall. The outlook is for embodied carbon and its successive lifecycle stages to become the bigger target for designers and engineers.

The strategies to cut embodied carbon are already well understood internationally. Drawing once more on MBIE’s work, Figure 3 groups these under three main objectives.

FIGURE 3:

Objectives and strategies to reduce whole-of-life embodied carbon

FMI Zero’s initiative for FMI Zero Waste fits under ‘Material Efficiency’. This objective is also where our efforts to ensure durability of our window and

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door frames sits—see our article on Page 40-41 on how we are building longevity into our insulated glass units.

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Could our FMI Zero Energy house be FMI Zero Carbon too?

Target BRANZ’s Carbon Budget project9 estimated the volume of carbon emissions that a newly built detached house could emit while still moving towards New Zealand’s net-zero goal for 2050. The answer was an ‘allowable’ total of 35 tonnes of embodied and operational emissions over a 90-year house life.

The researchers acknowledged this limit was likely to change as data capture and methods evolved.

They tested 10 real life newly-built houses and concluded that all exceeded the 35-tonne measure by several multiples, including builds whose building envelope surpassed the (old) H1 clause of the building code standards relating to energy efficiency. They noted,

Higher-performance houses are not necessarily low-carbon houses

Test limitations and parameters

We have said that definitions and measurements are a work in progress. The sustainable building scientists who we asked to test our FMI Zero Energy house for its net carbon emissions across its 90-year life could sensibly assess only a subset of stages. Specifically, they assessed life stages A1-A5, representing cradle to practical completion. For comparison to operational carbon, they also reviewed B6 for which they set the internal temperature to not fall below 180C; this is cooler than Passive House’s 200C but aligned both to an important NZ carbon research paper10 and to typical Kiwi occupant behaviour.

The biogenic impact of timber from sustainable forests was not included. Embodied carbon from appliances was also excluded. The latter was in

We felt there was a warning in those words for our FMI Zero Energy house, which is a 120m2 three-bedroom, single storey home, styled to suit Kiwi tastes. Our early focus was solely on the annual energy balance of this house in different local climates, and we gave little explicit consideration to the embodied carbon of the building materials chosen. Similarly, we ignored some Passive principles like window configuration, focusing instead on achieving high energy efficiency in the building envelope and allowing for renewable energy generation from solar panels on the roof.

If our FMI Zero Energy house was to pass as an FMI Zero Carbon house, it would have to do it by generating enough energy off its roof in the building’s lifetime to cover both the operational needs of the occupants and to offset all the embodied carbon including in the solar panels and fittings.

part because the embodied carbon of some items, for example the mechanical ventilation and heat recovery system, are currently unknown. Lastly, as a simplification regarding the embodied carbon in transport, each climate used the same value as that calculated for Auckland.

An important element in calculating operational carbon emissions was to forecast the mix of renewables in New Zealand’s grid. Our building scientists drew on data from BRANZ, selecting the Mixed Renewables scenario11 and extrapolating the last five years of data to 2050 out to 2111 for the 90 years of the house’s life. Emission values for LPG, natural gas and wood came from the NZ Green Building Council.

“A carbon budget for New Zealand houses”, BRANZ Research Now: Zero-carbon built environment #1, September 2020 Chandrakumar, C., McLaren, S., Dowdell, D., & Jaques, R. (2020). A science-based approach to setting climate targets for buildings: The case of a New Zealand detached house 11 https://www.branz.co.nz/environment-zero-carbon-research/framework/data/ Note that this data was refreshed in December 2021, but the update has not been incorporated into the results presented here 13 12

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Results Because of the transport simplification and because FMI uses the same FMI Zero Energy house design across all climates, the embodied carbon results were identical across New Zealand. The FMI Zero Energy house contains about 18.5 tonnes of embodied carbon, and Figure 4 shows most of this amount to be fairly equally split across the aluminium window frames, the steel roof and the aluminium Eurowood walls. Roof, walls, and floor have all been insulated with Heatlok HFO polyurethane foam which is also a significant carbon contributor for the house as a whole.

When combined with operational carbon, the FMI Zero Energy house’s total emissions in all climates are well above BRANZ’s 35 tonne limit. Figure 5 shows the total emissions ranging from 49 tonnes in climate zone 1 to approaching 55 tonnes in climate zone 6. The higher operating emissions load in colder climates is driven chiefly, and unsurprisingly, by the difference in overall space conditioning energy demand. The much greater heating demand in climate zone 6 more than offsets the higher cooling demand in zone 1.

FIGURE 4:

Embodied carbon by building component for life stages A1-A5 (Tonnes CO2 eq)

FIGURE 5:

Total carbon emissions by climate zone for FMI Zero Energy house (Tonnes CO2 eq)

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Solar power Where the FMI Zero Energy house comes into its own in terms of net carbon emissions is in the renewable energy off its roof. Even in the coldest climate, and allowing for the embodied carbon in the solar panels and their fittings, a modest 5.5W solar array putting out just under 7000 kWh can create enough surplus energy beyond the needs of the occupants to offset all the embodied carbon – see Figure 6.

The 17x 340W panels array modelled is similar to the one we proposed in the previous issue of Fenestration New Zealand where we used 18 x 300W panels on a slightly higher spec’d building envelope.

Installed, both these arrays cover a little over 31m2 which is slightly less than half the area of the sunny side of the roof. This leeway to add more panels matters for the reason explained next.

FIGURE 6:

Carbon balance for FMI Zero house over a 90-year life in Zone 6

Caveat Arguably, there is an issue with the international definition of Zero Energy houses when viewed through a Zero Carbon lens. A house meets the Zero Energy definition if its annual energy demand can be equalled or exceeded by its renewable energygenerating capacity. There is no requirement for battery storage to deal with short term or seasonal imbalances. Seen on a monthly basis, as in Figure 7, it becomes clear that in the warm months the house produces more energy than is needed, while in winter it must draw down on the grid which may be fuelled at peak times by fossil fuels.

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Battery storage to cope with seasonal imbalances would be expensive and, more importantly for an FMI Zero Carbon house, embody more carbon and use operating energy itself. Our FMI Zero Carbon house would need to offset the battery carbon with more solar panels to produce an even greater renewable energy surplus. We have comfort that this could be possible given the current modelled solar panels, even in Zone 6, cover scarcely half the north-facing roof.

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FIGURE 7:

Schematic of monthly energy demand in an energy efficient house12

Code versus FMI Zero The final insight into the feasibility of achieving FMI Zero Carbon came from using a carbon emissions lens to compare a new H1 Code-built house to our FMI Zero Energy house. As BRANZ has pointed out, houses with high thermal performance are not necessarily low in embodied carbon. Similarly, houses with poorer thermal performance in the building envelope can deliver lower embodied carbon. Clearly there is a sweet spot to be found, where the extra embodied carbon needed to deliver energy efficiency and energy generation is more than repaid in both the kilowatt hours saved over the life of the house and kilowatt hours returned to the grid13.

Figure 8 shows the differences in carbon emissions by type between the Code-built and FMI Zero Energy houses. The FMI Zero Energy house embodies about 15% more carbon, chiefly due to its walls. The aluminium wall cladding is a key source of extra embodied carbon and so too is the extra Heatlok spray foam needed to achieve FMI’s higher wall R value (3.3 versus Code 2.0).

The other aspect of note for embodied carbon in the FMI Zero Energy envelope is the larger profile size of a thermally broken window frame that contributes significantly to thermal performance. The larger frame profile results in a smaller glazing area, and this is enough to offset the higher embodied carbon of triple-glazed units. Consequently, glazing is almost the same for the two builds.

Operating carbon is two thirds less for the FMI Zero Energy house, reflecting the superior thermal performance. Total carbon emissions for the FMI house are consequently about half those of the Code house. And when solar panels are included, the FMI Zero Energy house achieves a 100% advantage over the Code house, even after allowing for the embodied carbon in the panels and fittings. In other words, our FMI Zero Energy design has proved it can qualify as FMI Zero Carbon. Henceforth, we’ll refer to the house simply as “FMI Zero”.

https://passipedia.org/basics/energy_and_ecology/primary_energy_renewable_per We are unsure how the FMI Zero householder might be compensated for surplus renewable generation beyond the few cents per kWh currently on offer from electricity retailers. The Emissions Trading Scheme (ETS) does not cover households. Currently, the point of obligation in the scheme occurs as far upstream in the supply chain as possible 12

13

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FIGURE 8:

Lifetime carbon emissions by type for New H1 Code-built and FMI Zero houses (Tonnes CO2 Eq)

Optimisation The difference between FMI Zero and the Code house on embodied emissions is relatively small at about 15%. We suspect that with a few adjustments the embodied carbon of our FMI Zero house could be reduced to match or surpass the Code house given that we did not consider this aspect in our original FMI Zero Energy design.

It is tempting to think that a design focus optimising operational carbon is the better path to lower lifetime carbon emissions for New Zealand houses. As the years go by, operational carbon accounts for an everlarger share of a home’s carbon emissions (Figure 1), making it the greater prize. In our FMI Zero house, it represents about 65% of lifetime emissions and is the

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source of the significant carbon emissions advantage over the Code house, coincidentally also about 65%. However, we recognise that results may shift as measurement of embodied carbon develops and once all stages of the building’s life cycle are able to be included.

In this article we have focused on understanding net zero carbon, its components and how different house designs, including our own FMI Zero approach, stack up. Further optimising would consider the relative costs and payback of reducing embodied and operational carbon, and of being paid for creating surplus renewable energy.

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Less cold, less mould

When designing homes, we determine whether we’ve done a good job by assessing things like health, comfort, and energy efficiency. But as an industry, there’s one metric we tend not to do well on in New Zealand – that’s mould. The 2015 BRANZ house condition survey found nearly 50% of homes had visible mould.

Growing mould For mould to grow inside our homes, it needs a high enough relative humidity in a reasonable temperature band. A rough rule of thumb when it comes to mould is “cold spots equal mould spots”. If an indoor surface is colder than the room temperature, it cools the air immediately adjacent, raising the local relative humidity. As an example, assume the warm and dry air inside a typical New Zealand home in the winter is 20°C at 60% relative humidity. If the surface is only 15°C, the relative humidity will be over 80%, which is a great breeding ground for mould.

So, it’s not just temperature and ventilation – the interrelation between the indoor relative humidity,

1

https://sustainableengineering.co.nz/fuel-poverty-impacts-mental-health

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air temperature and local surface temperature is one more dynamic to manage. To prevent the conditions that allow mould growth we need all three of adequate heating, sufficient ventilation, and high enough surface temperatures.

Researchers like Professor Philippa HowdenChapman and her colleagues at the University of Otago1 have made it abundantly clear how important it is for us to heat our homes in winter for our health But heating our homes to 20˚C is not sufficient by itself; we also need to ventilate sufficiently and keep surfaces warm enough.

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fRSI What is a warm enough surface temperature to prevent conditions for mould growth? That depends on the indoor relative humidity and air temperature.

In Europe they use a metric called fRSI or the ratio of the indoor local surface temperature to the indoor to outdoor air temperature. It ranges from zero to one, with one being a perfect match between the indoor surface and indoor air temperature and zero being

when the indoor surface is the same temperature as the outdoor air.

This ratio is fixed for a specific building construction like a window installation or wall-to-floor junction.

The illustration below in Figure 1 is for a thermally broken window and shows the cold interior surface with a fRSI=0.31.

FIGURE 1:

Temperature ranges across a thermally broken window frame

Is a fRSI=0.31 good enough to stay outside the mould zone? If we know the surface temperature and heat the home to 20˚C, we can perform a moisture balance

test (with a typical occupancy) to find the required minimum fRSI to hit the mark.

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Air Changes Almost there! One more factor that is relevant is the average ventilation rate in our home over the winter. This is measured in ACH or Air Changes per Hour. If the total volume of air in your home was turned over in one hour that would be 1.0 ACH; if the air turned over in 10 hours, it would be 0.1 ACH. What’s typical depends on who you ask but research2 on modern homes in New Zealand found a range that went all the way down to below 0.1 ACH. Overseas, a common requirement for continuous mechanical ventilation is set at 0.3ACH and this requirement has been adopted in Homestar V5 in New

Zealand – I’d like to see it in our Building Code too.

Continuous mechanical ventilation means you know the ventilation rate, which is needed to determine if your fRSI is sufficiently high. If you only use windows for ventilation, it depends on how much you open them when it is cold outside. Keeping those windows shut means a low ACH. Figure 2 below shows examples of what fRSI is adequate for our various climate zones. If we heat our homes to 20˚C and predict our ventilation rate, then we can say yes or no to that fRSI.

FIGURE 2:

Minimum fRSI required by climate zone at different ACH levels

From this chart, we can say that the fRSI=0.31 modelled in the thermally broken window above is not acceptable as it permits the growth of mould over all

the ventilation rates and locations given. We need a fRSI of at least 0.35 in Christchurch.

Lifting fRSI We can easily achieve higher fRSIs through changing our building design and construction practice. For example, we can recess the thermally broken window frame into the wall along with better flashings. This change will hit a fRSI>0.4 and avoid creating the low surface temperature that allows mould to grow.

What if your house design or location means you need a higher fRSI? Then the answer is a better thermally performing window frame like a better designed thermally broken aluminium frame.

build our homes, we can prevent the conditions that encourage mould growth.

Yes, it is another complexity to manage, but with the right information we can simply adapt our designs and construction techniques to get the homes we deserve – ones that keep us warm, dry, and healthy.

This same fRSI logic can be applied beyond this window example to all the construction details in our buildings. If we heat our homes, ensure adequate ventilation (and we now know what adequate is) and control surface temperatures by improving how we 2

http://hdl.handle.net/2292/21764

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Durability = Sustainability

Energy efficiency is often the first thing discussed when it comes to sustainable design. What is often forgotten is durability. But what good is energy efficiency in a building if it doesn’t last?

Consider glazing systems: The insulating glass unit’s (IGU’s) lifetime, along with accompanying window gaskets and seals, is generally the determining factor in an aluminum window’s and curtainwall’s lifetime. According to Graham Dodd from Arup, the lifetime of an IGU currently is expected to be 25 to 40 years1, which is quite a large range (figure 1). Given the critical nature of fenestration in the building envelope, the longer the lifetime of the IGU, the more sustainable the building itself is likely to be.

There is a lot of pressure to improve the energy performance of fenestration through using inert gases, triple- or quad-pane configurations and warmedge spacers with incrementally improved thermal performance. When making such decisions to change the design (or processing) of an IGU, the first question to ask is: Will this change negatively impact the IGU’s durability and potential lifetime expectations? That is often a hard question to answer, but there are several insights that can be gained from IG testing and certification.

Desiccant absorption capacity of the IGU is a good place to start. The Insulating Glass Certification Council’s (IGCC) IG Certification program requires manufacturers to declare the Absorption Capacity 1

Helen Sanders, PhD, General Manager Technoform North America

per Foot (ACPF) of the edge spacer. The value depends on the amount of desiccant that is physically incorporated into the spacer and its percentage absorption capacity by weight. All other things being equal––moisture ingress rate, unit size, etc.––the more desiccant capacity there is in the edge seal, the better it will do in durability testing and the longer the IGU should last. APCF gives a value that can be used to provide a first level comparison between different

G. Dodd, Design Freedom and environmental performance beyond the constraints of the hermetically sealed insulating glass unit, Proceedings of GlassCon Global 2018, p101.

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edge seal systems, including between those with loose and integrated desiccant.

However, since “all other things” generally are not equal and moisture ingress rates change through weathering and vary across different edge seal materials, designs and manufacturing processes, IGU seal testing is another way to assess the relative durability of different IGU designs. Because the ASTM E2190 IGU durability performance specification only gives a pass or fail target for dew-point (<-400F) after weathering, it does not provide insights as to the relative margin by which IGUs pass the durability test.

However, some manufacturers will put the same set of IGUs through the ASTM E2188 15-week weathering protocol multiple times to assess time-to-failure as a way of comparing the performance of a new edge seal designs or processes to a previous benchmark.

Another way of assessing relative durability performance is to measure the moisture uptake of the desiccant in the IGUs after testing and compare it to the moisture content of desiccant in an unweathered IGU made at the same time. The lower the uptake, the better the IG seal is at keeping out water.

This is standard practice in the European EN1279-2 IG weathering test, which allows direct quantitative comparison of the moisture barrier performance of different IGU seal systems and an assessment of the margin by which the performance bar was surpassed.

When considering design and processing changes to IGU systems, improving durability is as important as improving thermal performance. The long-term thermal performance of an IGU is only as good as its durability, and the sustainability of a building is only as good as the durability of its glazing.

FIGURE 1:

Example of an insulating glass unit at its end of life.

Photo courtesy of author

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Durability, not just performance

Twenty per cent. That’s an estimate1 of the share New Zealand’s building and construction sector bears of this country’s greenhouse gas emissions of carbon dioxide and equivalents (“carbon” for short). Twenty per cent is a figure to focus anyone’s mind, not least against the target of this country reaching net zero in off-farm emissions by 2050 and needing to navigate a series of 5-year emission-limiting budgets to carry us there.

A key source of emissions for the building sector, and now receiving more attention, is embodied emissions.

These come from the carbon associated with making,

transporting, and removing the materials needed to build, maintain, and eventually dismantle any building.

Construction materials that help reduce embodied emissions will contribute to dialling back that twenty per cent.

At FMI, we started with a focus on achieving net zero in the energy used to run a house during its life as is evident in our research into the feasibility of Zero Energy homes. Operating energy creates operational emissions. Of late we’ve been shifting gears to more carefully consider embodied emissions and the levers that can drive carbon out of the life cycle of a house.

Durability The construction phase of a house is typically the main source of embodied carbon. It’s therefore not surprising that Building for Climate Change’s framework considers upfront house design, material selection and waste limitation as key levers. However, it also mentions “long-lasting” in terms of the useful life of the house and its materials, and this is where our recent efforts in window and door systems have been focused.

High-performance windows are the most effective addition to a building envelope to cut heating

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demand, but how long do they last? If they need replacing after a decade or two, not only do the new ones increase the embodied carbon in the home, but the original windows’ waning energy performance will also have increased the operating emissions for a period. Progressive improvements to the thermal performance of windows through innovations like inert gases and warm edge spacers should not come at the expense of the windows’ durability. The answer lies in testing for durability in parallel with R&D that is designed to lift thermal performance.

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Early testing New Zealand homes have only a short history, perhaps thirty years at most, of using insulated glass units (IGUs) such as double-glazed windows. Early domestic output struggled with durability due both to manufacturing inexperience and installation issues.

Warranties were consequently short, rarely reaching five years.

Late adopters benefit from offshore learnings, however. In the early 1990s, the local industry organised itself to research the causes of its IGU difficulties and to choose the most appropriate international durability testing standard to support

improvements in local quality. BRANZ, as an independent third party, initially administered the chosen British BS 5713:1979 standard2 across all manufacturers. By 2000, the industry had largely moved to the European EN 1279 standard which incorporated further important contributors to long term performance. The European standard added, among other things, testing for inert (argon) gas losses from between the panes in an IGU, and assessments of day-to-day manufacturing quality control. The industry continues to cherry-pick the best of international standards and to apply them in combination in various performance tests.

Quality The objective of IGU testing is to provide a consistent assessment against accepted standards of the performance of components like edge seals and spacers. Climate tests mimic the stress of weathering conditions, for example. Some units from a batch of samples are taken apart to measure aspects like moisture level in the spacers’ desiccant. If they pass this initial moisture test, the remaining units undergo long-term climate testing. Similar moisture level measurements follow, with Pass or Fail grades issued.

This kind of testing is valuable: manufacturers lift

1 2

their game to deliver quality and consistency, and customers are reassured their window system supplier has met the grade.

Indeed, improvements in local quality and manufacturers’ confidence in their processes are reflected in the doubling and even tripling of doubleglazed window warranties now being offered. No doubt many window systems last much longer than the warranted ten to twelve years.

“Whole-of Life Embodied Carbon Emissions Reduction Framework”, MBIE, August 2020 https://www.buildmagazine.org.nz/index.php/articles/show/developing-local-igu-tests

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Going beyond Tests for quality and consistency do not necessarily support developments to help reduce embodied carbon, however. In particular, the current testing regime does not provide guidance on how long an IGU will last. The IGU samples are taken apart after a set period of testing; they are not tested until they fail under repeated stresses. Also, in some parts of testing, performance is simply graded Pass or Fail without accompanying measures to indicate how close to failure a unit has come.

FIGURE 1:

Views of a high humidity chamber

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At FMI we have taken a different approach and one we believe to be the most advanced in New Zealand.

We already have high humidity and volatile fog chambers (Figures 1 and 2). To these, uniquely, we have added an accelerated weather chamber (Figure 3) and are able to identify the durability in years of an IGU unit by testing it to destruction rather than destroying it before it has in fact broken.

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Accelerated weather chambers are a feature of long-term climate durability testing under the ASTM standards operating in the US. The sequence of the

stresses ASTM requires to be applied to IGU units, and which we can now replicate, is listed below:

First Step: High Humidity Chamber

Third Step: High Humidity Chamber

• Test Constant Spec: +600C @ 95% relative humidity • Test Time: 14 days (336 hours)

• Test Constant Spec: +600C @ 95% relative humidity • Test Time: 28 days (672 hours)

Second Step: Accelerated Weather Chamber

Volatile Fog Chamber for Pass / Fail

• Test Cycle Spec: cycles of 252 @ -290C to +600C, with ultraviolet lamps & water mist • Test Time: 63 days (1,512 hours)

• Test Constant Spec: +500C @ +21 cooling plate • Test Time: 7 days (168 hours)

FIGURE 2:

Views of a volatile fog chamber: closed and in operation

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Our testing set-up thus allows us to test to both New Zealand and international standards. Once we are accredited by IANZ, which we expect to have accomplished within the next six months, we will be

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able to credibly compare the durability of our products with other manufacturers’ as per testing standard requirements and our subsequent testing that goes beyond.

FIGURE 3:

Views of an accelerated weather chamber, before and during testing

Sweet spot While we await accreditation, we have been busy comparing the durability of different inhouse combinations of spacers, sealants, and desiccants in our high-performance windows. We have found optimal “recipes” that last twice the time of our window models that have already met the official EN 1279-2 standard for moisture penetration.

The upside for windows with XR Edge insulated glass units to assist New Zealand in driving down both operational and embodied carbon from new build homes is exciting.

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WHO WE ARE Proudly Kiwi owned, FMI Building Innovation is a strong family of interconnected brands offering exceptional building solutions to architects, builders, trade customers, and our very own extensive fabricator network across the country.

For over 54 years we have been New Zealand’s leading supplier, manufacturer, and innovator of world-class building solutions.

We have four channels to market brands that allow our customers a full service solution experience: Eurowood, Fairview, Next and Vetro Raccordi. Across these channels we supply some of New Zealand’s finest building materials for applications across thousands of Kiwi homes and industries.

We have locations in both the North and South Island of New Zealand that total 46,000 square meters of building space, spanning across 9.2 hectares of land.

Over the past 54 years, our customers have come to know us as industry innovators. We’re always looking forward, pushing boundaries, and pioneering improvements in products through sophisticated research and testing.

But the true essence of our company is our people.

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The ingenuity and passion of hundreds of our fellow Kiwi workers have driven our energy to strive for better solutions, and helped shape the exceptional business that we are today.

OUR HISTORY My late father, Peter Lewis, started Fairview Metal Industries (FMI) in 1968 when he bought a steel manufacturing plant in Timaru.

His resilience and spirit were tested when the factory burnt down three months later.

Never one to give up, Peter and his team worked through a bitter winter to rebuild the factory and grow the company that we know today.

Over the past 54 years we have built a strong reputation for exceptional quality products, and genuine innovative thinking.

Every day, we deliver truckloads of injection moldings, aluminium extrusions, glazing, and more, for applications across thousands of New Zealand homes and industries.

Today, we are one of New Zealand’s leading suppliers of innovative window, door, and glass manufacturing solutions.

But at the end of the day, we’re a family

company that ultimately understands the importance of what it means to have a sense of belonging and a place to call your own.

Warren Lewis – Managing Director

09 574 2900

www.fmi.co.nz 49

THE BEAUTY IS IN THE

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