PHINZ has created a short guide to help with terminology when talking about projects that our members and other Passive House professionals undertake.
While PHINZ is focused on the Passive House standard, and other PHI standards, we know that not all projects are certified Passive Houses and that conversations regarding better performing buildings often seek to make comparisons.
This guide includes additional terms, common in the construction industry, to guide these conversations. The terms themselves and how they are used are not governed by PHINZ. We have included them in this guide to provide context, and to help members, sponsors, clients and journalists on Aotearoa’s journey towards the Passive House standard.
The guide is free to access on the downloads page or directly by clicking on the image below.
Please share the guide widely to support clarity around how we all refer to projects and understanding of what a Passive House project is. Greenwashing does no one any favours.
We also encourage Passive House professionals and others to read “Claiming the Passive House Standard” available on the downloads page. This covers legal aspects of false claims relating to use of the term “Passive House” which is protected in consumer law.
We may seem a bit late to the party since Homestar v5 was launched in 2021! However, Homestar v5 is due to come into force in February 2023 so we’d like to share some of our thoughts on it.
Homestar and Passive House – what’s the difference?
First, it’s important to acknowledge that Homestar and Passive House are quite different, but at the same time can be complementary programmes.
- Homestar is a broad green building rating system with many categories created for New Zealand homes that is administered by the New Zealand Green Building Council (NZGBC). Categories include, for instance, daylight, water conservation, appliance efficiency, resource efficiency, healthy materials, VOCs, construction waste, and embodied carbon. Accredited professionals design and certify Homestar projects.
- Passive House is an international standard for comfort, health, and energy efficiency that can be applied to almost all building types, not just homes. The standard is administered by the Passive House Institute in Germany, but accredited New Zealand professionals design, construct, and certify Passive House buildings here. PHINZ advocates and provides education and resources (including software) to promote and encourage the uptake of Passive House in New Zealand.
While Passive House is a standalone standard with many benefits, it also provides an excellent building-science and evidence-based foundation for any sustainable building by ensuring some core fundamentals are rigorously taken care of. This is recognised by NZGBC and a certified Passive House project will gain many Homestar points (mainly energy, comfort, ventilation, and moisture credits) assisting it on the way to a high Homestar rating. Passive House tools have also informed the latest version of Homestar – more on this below.
We were pleased to provide detailed feedback on proposed updates from Homestar v4 to v5 and see some of our suggestions implemented. Here are seven things we love about Homestar v5:
- Greater emphasis on thermal comfort and energy efficiency. These are core fundamentals that every building really should be achieving. It is an indictment of our traditionally poor building standards here in New Zealand that the majority of buildings fail to do so and people have to rely on voluntary programmes like Passive House and Homestar for these to be properly addressed.
- Energy modelling is prioritised. At the core of any high-performance building that achieves high thermal comfort and energy efficiency is rigorous energy modelling. It is a critical tool to guide the design and ensure building science underpins decisions about orientation, thermal insulation levels, glazing areas, configuration and performance, ventilation strategies, etc.
- NZGBC has created its own energy modelling tool, the Energy and Carbon Calculator for Homes (ECCHO), based on the Passive House energy modelling tool, the Passive House Planning Package (PHPP.) The PHPP software has been developed for over 30 years incorporating feedback from the monitored performance of completed buildings and feedback from dynamic modelling tools. It has been simplified enough to make it a highly effective design and certification tool while not losing any of its accuracy and rigour. We expect that the ECCHO tool will be invaluable for assisting Homestar-certified projects to achieve higher energy efficiency and a reduced performance gap, even when they don’t also target or achieve Passive House certification. PHPP can also be used for Homestar, as it can for NZ Building Code compliance (but note the following point.)
- It sets absolute energy intensity caps for thermal performance of the whole building, like Passive House has an annual heating demand limit of 15 kWh/m2. This is in contrast to a “two-model” or “reference model” approach, which the NZ Building Code H1 modelling method currently uses. In the “two model” approach, an improvement over a reference model based on elemental minimum compliance settings is required. This incentivises designing buildings with poor thermal performance as they are easy to show an improvement on. This is a well-established issue and Passive House Canada set it out clearly in this linked article. Setting absolute caps or targets overcomes this issue and it is what we must do if we are serious about reducing energy use and operational emissions from buildings.
- Addresses moisture control at junctions. Surface condensation and mould are prevalent in New Zealand housing, sadly, and often it can be due to thermal bridging at construction junctions or poor window details. Homestar now includes fRsi requirements for junctions, adopting the Passive House (PHPP v9) requirements. The freely available High-Performance Construction Details Handbook provides fRsi values for a catalogue of details, as well as the PSI values for heat transfer.
- Requires pressure testing, aka Blower Door Testing, for 8 Homestar rating and higher. It is good bulding science and widely recognised that reducing uncontrolled air movement (aka infiltration, exfiltration, airtightness) through the thermal envelope is critical for moisture protection and energy efficiency in buildings with high thermal performance. Homestar sets targets as infiltration per square metre of thermal envelope, rather than air changes per hour that Passive House uses. Both results can be derived from the same testing procedure, though.
- Addresses important aspects of sustainability that Passive House doesn’t. Passive House has a relatively narrow focus on the core fundamentals of building performance so there are many aspects of sustainable design it doesn’t cover and we don’t expect it ever will. This is arguably one of its strengths and a reason why it is so successful at delivering what it promises and eliminating the performance gap. This doesn’t mean other aspects don’t need addressing also, though, such as daylight, water conservation, appliance efficiency, resource efficiency, healthy materials, VOCs, construction waste, and embodied carbon, for example. Homestar provides a complementary framework to address these and many other aspects of sustainable design.
Homestar and Passive House crosswalk
NZGBC and PHINZ have worked together on a Homestar and Passive House crosswalk. This provides detailed guidance on which Homestar points and credits a certified Passive House project can acheive to promote and support dual cerrtification. When the crosswalk is published, it will be availabe on our downloads page and a direct link will be added here.
Other green building organisations have also set out how Passive House is complementary with their rating and created crosswalks. We are aware of the following:
- Green Star – Design & As Built (Aus) and Passive House (or download the crosswalk document directly as a PDF)
- LEED and Passive House
- ILFI Zero Energy and Passive House
- Klimaaktiv and Passive House (German language)
The international Passive House Association also maintains a page on crosswalks that may be more up to date.
Adele Eyers, originally from South Africa, has her own construction project management consultancy and in the last three months has been concentrating on the other side of the coin – an apprenticeship in building. PHINZ would like to roundly congratulate Adele on being the first female to become a Certified Passive House Tradesperson in Aotearoa NZ, having recently passed the CET course. We caught up with Adele to chat about her experience.
What motivated you to become involved in construction and in Passive House?
I’m a construction project manager and have my own consultancy company, and I hit a moment in life where I wanted to jump to the other side and pick up the tools. I also have a brother and sister-in-law who are very passionate about Passive House, so it ended up being the natural route to go. Once you go through all the literature for studying building you realise it’s best to start at the Passive House end, finding out the right way to build, and then layering the Building Code onto that, it becomes impossible not to want to build better.
What are your thoughts on the broader state of construction in Aotearoa?
Just speaking for the bigger construction companies that I’ve worked for in the last couple of years, you can see they are wanting to do the right thing and learn new ways, which shows a definite upward trend in the right direction.
For the younger apprentices getting into the industry, the earlier in their careers that they can get into Passive House and the science behind it, the better – because they’ll drive the new generation.
How did you get on with the PH Tradesperson course?
It was quite challenging mentally – refreshing to be that challenging though! It wasn’t a given that you were going to pass – you had to understand it and do the calcs in real life scenarios or you wouldn’t pass. It was a good combination of practical and theory. It was very mathematical, which I like, and it got the brain working. I can see that it will be good knowing the building science behind it and how the calculations work to help moving forward.
What’s it been like being a strong female in the NZ construction industry?
Generally I feel supported. The attitude to females working in the construction industry in NZ is certainly better than in South Africa. I currently work with a great team who value my input especially on the Passive House detailing since completing the course. There are lots more females in the trade (sparkies, plumbers) now. But I don’t deny there is still old school thinking regarding females for a small number of the older generation in the industry. The younger generation though is much more about equality. It’ll take time, but it’s getting there. And for my part, it’s a mindset to get through your apprenticeship but I definitely make sure people don’t walk over me.
What would you say to other wahine thinking about getting in to the industry?
Just do it! If you have a hint of wanting to get into the industry and your doubting it, don’t over think it. Just do it. The support will be there, one way or another you’ll find it.
Any thoughts on where to from here for you?
I always thought I knew the answer: that I’d be expanding my project management consultancy in a particular direction, but now after doing the Passive House course I’m not so sure. I’m going to concentrate on getting the building apprenticeship done as quickly as I can, and then it’s brewing in the background to expand into a more Passive House line. Possibly an idea around building a supportive network for female tradies. It’s brewing!
What do you feel you got out of the Passive House course?
This course has taught me how important airtightness is in a house. Having built a beautiful home, designed by my sister in law Jessica Eyers from Hiberna 5 years ago, we then sold to move to Wanaka. Our current house, built in 2011, is the best we could afford at the time, and the quality of the build is terrible. I would urge people to think long term – invest early on and do it as good as you can, because you’re only going to do it once. Some people build houses that incorporate “some” aspects of Passive House – you spend a lot of money in intello and tape and detailing, but you still have thermal bridges, so you don’t end up with a house that performs as you expected in your mind. They go part way – I would recommend doing it right and going the full distance as you’ll be spending the extra in wasted energy costs on a part-way build over the next years anyway.
PIHA HOUSE started in 2019 as pretty much a standard renovation of an existing 2012 build, using European quality exterior joinery and more insulation. Although the brief was not Passive House quality, it was continued work for myself and team, considering I am a Certified Passive House Builder.
Work started, removing interior linings to add extra insulation and hello, we found mould, particularly in the closed cell roof cavity, but also in the walls.
As we now know, dew point is real and really brings home the problems it can cause if positioned in the wrong place, or allowed to be positioned in the wrong place.
As my client had health problems associated with mould sensitivity, the only way forward was to reassess and consider Passive House construction.
The decision was very quick, YES !!! No other way.
As this was the first EnerPHit project in NZ, we were definitely in a new space, but very exciting at the same time. Who doesn’t love a good challenge with something you are passionate about?
The construction was really so much fun, testing us at every corner, but with the end result in the back of your mind all the time, WILL WE GET CERTIFICATION, is a huge driving force.
One of my guys, Visko, spent six weeks air tight taping exterior protrusions from the treated area envelope to the exterior, probably using 60 rolls of Proclima Tescon Vana tape.
During the process of the job I was lucky to be able to purchase a second hand Blower Door kit, this was invaluable to check our work as we progressed.
One very significant piece of this job was the interaction of upper floor exterior concrete decks above treated floor areas below.
To mitigate thermal bridging, 80mm insulation board was glued to the underside of the concrete decks with 20mm EPS board glued onto the walls, 600mm down from the ceiling, Jasons Quinn’s calculations and thermal bridging imaging gave us this specification. Also to mitigate dew point on the interior between the underside of concrete and the insulation board, the ceiling was suspended allowing for the ventilation return air to permeate through this cavity, we also integrated a baffles system, basically a labyrinth of wads at one metre centres running the length of the enclosure with a gap in the centre of the first wad and then a gap at each end of the next wad and so on. This made the air flow encompass the whole space instead of making a one track to the return pickup.
Actually, this was my clients idea, brilliant idea.
As this was an existing concrete block, two story solid plaster exterior painted finish, Jason advised that we would use the painted plaster as our air tight wall barrier, and the existing bitumen membrane roof as the roof barrier.
Exterior insulation was installed over the outside of these existing claddings, wall cladding continuing down to the foundations to a minimum of 600mm below floor slab height.
So, Stotherm with 100mm Graphite board and 160mm warm roof with bitumen Nuraply.
As my clients are very natural product driven, the interior was all timber types, coated with non toxic products, Osmo being the most used.
The job was completed in February 2022 with CERTIFICATION !!
I would thank all involved. What a project!
Piha House EnerPHit can be viewed here on the Sang Architects website.
Progress in teaching clients the importance future building technology offers, has been quite slow over the last ten years, but noticeable interest gaining each year, to the point now that the Government are building Kāinga Ora developments to Certified Passive House standard. This in turn is directing Standards NZ to adopt climate zoning for insulation values, next in line is exterior joinery. Before you know it, Passive House will be the new NZ build standard.
-Terry Bryers, Bruyere Ltd
As interest in better performing buildings, and Passive House specifically, is ramping up rapidly in Aotearoa NZ we are starting to see dubious Passive House claims being made more frequently (and more complaints about incorrect claims coming our way).
Be mindful: if your build has not reached Passive House certification, then you cannot claim it as Passive House.
Further to this, confusion over the term Passive House is also increasing. In the media we are seeing the terms “Passive House principles” and “Passive House techniques” used with increasing frequency.
The Passive House Standard is an as-built standard, not a set of principles, just as the Building Code is a set of standards to comply with – so if you’re unsure of how to use the terminology, simply substitute the term “Passive House Standard” with “The Building Code”. In this way, you would never say “Building Code techniques”, and neither would you do so for Passive House. Problem solved!
It is vital to protect the integrity of the standard and the value proposition of Passive House by always using clear and accurate terminology. This also protects the interests of our members, the wider Passive House whanau, and consumers.
Please refer to the members code of conduct for more details about accurate terminology – and remember that inaccurate claims leave the parties involved open to legal challenge as the term “Passive House” has consumer law protection as set out in our free downloadable guide “Claiming the Passive House standard”
What are the important things that make your life comfortable..healthy…happy? If you scaled that idea up to your community, have you ever thought what that community might look like? Would it be a place where you’re not shivering by a fire at night so you don’t spend too much on power? Or where your child isn’t coughing from the mould in their bedroom or the condensation down their windows in the morning? Or would it be walking into a school or workplace in winter and staying comfortable all day so you can think on more important things? In that community, would it be taken for granted that everyone naturally had access to that comfort and health?
We wanted to find this out too, and to see what differences were being made in the community by doing the Passive House courses at the ground level. What we received was an inspiring insight from Certified Passive House Tradespersons Glenn Harley from Harley Builders and Lenny Basham from Basham Building Ltd
Here’s what Glenn had to say….
“By the time I signed up for the Passive House Tradesperson course, our company had already completed a couple of Passive House projects. The course offered by PHANZ dovetailed (sorry) nicely with the practical realities of a Passive House build. I found the opportunity to calculate U values of various building materials interesting and applicable. We got a window (there I go again) into European building techniques and products.
Kara has a witty and direct style honed from many years of teaching people how to build better. She is a fantastic resource available right here in Aotearoa.“
And Lenny highlighted how the CET course made a tangible difference to him and his business….
“As a passionate carpenter, I would highly recommend the Passive House Tradesperson Course. Previously, I had attended a Primer in Wellington. So I thought I had a reasonable understanding of what a Certified Passive House was. However, after completing the course, I had a much more comprehensive knowledge base on all things Passive and a lot more confidence in the field.
There have been many benefits to completing this course. It has enabled me to have educated debate with designers and engineers on how a building will perform. This has allowed me to dictate material choices and approaches to design. These professionals have been grateful to have someone that knows about thermal bridging or allowing for services such as ventilation in the design stage. This has then made the build easier.
The course gave me knowledge so that I have been able to work with designers in the certification process of a Passive House. We would’ve missed a heap of documentation such as key photos or detailing around airtightness if I had not completed the course. This would’ve been costly financially or we wouldn’t have a building that achieved Passive House standard.
Another bonus has been the ability to impress clients on how a home can perform and school them up on Passive details and design. That has seen me win a couple of tenders where competitors didn’t know about heating demands and the importance of good design.
The whole concept of a Passive House can be quite daunting at first. There’s so much detailing and numbers to get your head around compared to a standard build. A lot of it is quite intellectual and scientific. As a carpenter, you wonder what its relevance is, when all you want to do is build a quality home? The course helps bridge the gap between the design nerds behind the numbers and the fellas onsite who actually create the beast. The CET Tradesperson course gives you confidence to navigate through the whole process and it would simply be a whole lot harder to build a Passive House if you didn’t school yourself up first and do the course. I highly recommend it.”
The next in-person Certified Passive House Tradesperson’s course is happening in Auckland in May. You can find all the info on this, along with courses for Designers and Consultants at phanz.co.nz
You can also find Certified Passive House professionals in your area by heading to our members directory and filtering by “Certified Passive House Professionals”
Be part of the change.
Kia ora koutou,
As we approach the end of 2021, I’d like to thank you for your energy and passion in driving the Passive House kaupapa, and your support of PHINZ.
We’ve seen huge momentum this year for Passive House in Aotearoa.
These projects are a huge step towards making Passive House accessible for our most vulnerable, and in providing learnings to the industry.
Toiora High Street Cohousing in Ōtepoti Dunedin achieved its Passive House certification this year. The Bushland Park subdivision in Ōtautahi Christchurch is now underway, and construction began on the Luggate Hall Community Centre in the Queenstown Lakes area. Threepwood Passive House has picked up two prestigious Te Kāhui Whaihanga NZIA awards this year, the 2021 Southern Architecture Awards and the Housing Category of the Architecture Awards.
There are now 66 certified Passive House dwellings across the country, and many more in the pipeline.
Back in May, Minister for Climate Change James Shaw highlighted Passive House as one of the voluntary standards homebuilders wanting an energy efficient and lower-carbon house could use today. And last month, the recent update of the Building Code now recognises the Passive House Planning Package (PHPP) as a modelling tool that can be used as a means of compliance.
The PHINZ Board welcomed Nick Manarangi and Glenn Harley this year, and we farewelled Andrea Stocchero and Matthew Cutler-Welsh. Thank you again Andrea and Matthew for your valued contribution. We now welcome Murray Robertson to the Board, and to the position of Board Chair. Happily Elrond Burrell will remain on the Board but step down as Acting Chair.
Amanda Lowe joined as our administrator in March and has been invaluable support to me and the Board and I am sure to many of you.
We enjoyed a busy Hui weekend at Victoria University in Wellington in June, and plans are afoot to mix things up a bit next year – watch this space.
We were so disappointed to have to postpone the South Pacific Passive House Conference 2021, but happily almost all the speakers and planned attendees have been able to make the new dates, we have reopened registrations, and we can’t wait to see you all there.
This year we’ve been participating in the International Passive House #EfficiencyFirst campaign, which advocates for focus on using less energy in the first place before focusing on renewables. Dr Michael Jack from the University of Otago represented PHINZ at COP26 on this topic, discussing how smoothing of peak energy loads is vital in reducing overall energy requirement.
PHINZ membership has grown rapidly by over 40% since the start of 2021 – we are almost at 200 members. And this year we gained our first annual sponsors and are now up to 8 – we are so grateful to you all!
Wishing you, your whānau and communities a safe, happy and healthy Christmas break, and I look forward to reconnecting in the New Year.
Ngā mihi nui
On 29 November, MBIE released the 2021 update to the building code. The main changes include increasing insulation requirements and changes to Acceptable Solutions and Verification Methods.
However, quietly tucked way in H1/VM1 Energy Efficiency Verification Method is a section that now recognises the Passive House Planning Package (PHPP) as a modelling tool that can be used as a means of compliance.
This is really exciting because although the methods required for compliance with the Building Code still leave plenty to be desired (read out position paper here), PHPP is a reliable and accurate modelling tool when used correctly. Passive House designers and consultants receive training in the use of PHPP as part of their CEPH2 course and some of them offer it as an independent service – see certified Passive House designers and consultants here.
If you want to buy a copy of PHPP, we are a licensed reseller and you can purchase it from our online shop.
Watch this space for a further info and events relating to PHPP!
Ngā Kāinga Anamata, which means “homes of the future” is a Kāinga Ora project aimed at driving carbon emission reduction in New Zealand’s construction industry.
The project will deliver 30 new homes within five, three-level apartment buildings in Auckland’s Glendowie. Each near identical building will use a different construction technology, enabling insights to be gathered on a range of building materials and systems.
- Mass timber / cross laminated timber (CLT)
- Light timber frame (LTF)
- Precast concrete
- Light gauge steel
- Hybrid CLT / LTF
All 30 homes will target Passive House certification.
The project team expects the homes will meet all performance caps outlined in MBIE’s Building for Climate Change (BfCC) programme, and that it brings the Ministry for the Environment’s draft Emissions Reduction Plan (ERP) to life. The knowledge gained from this project will enable and catalyse change in the building industry, demonstrating how meeting the Passive House standard and the BfCC’s targets can be achieved. Hon Dr Megan Woods, Minister for Housing, Energy & Resources, and Research, Science & Innvovation, says “This project will shape the way for the construction industry in Aotearoa New Zealand.” and says that the project is “Validating MBIE’s policy assumptions and demonstrating to industry that future carbon emission targets can be achieved using construction materials and systems that are available today.”
Kāinga Ora Commercial Director Matt Noyes acknowledged PHINZ’s support of the project thus far, and that of the Project Partners, including PHINZ members Context Architects (Project Architects) and Sustainable Engineering (Passive House Certifiers for the Project).
Brian Berg, who leads the Carbon Neutral Housing Team at Kāinga Ora says that Passive House was chosen for this project because it is an industry ready solution, and this played a big part in de-risking the project for Kāinga Ora’s investment. The evidence-based approach taken for the design of the project also meant Passive House was the obvious method to use. The combination of Passive House and the use of local renewable energy means this project will be net zero energy.
The use of industry ready solutions and processes was a big contributing factor into the project’s inclusion in the prestigious United Nations Climate Conference (COP26) Build Better Now Virtual Pavilion. The project is one of only 17 initiatives globally to feature in the pavilion, running from 31 October – 12 November buildbetternow.co .
Matt Noyes says “The homes we build today will set the path for our carbon emissions in the decades to come. We need to be part of the solution, driving innovation and transformation now to ensure good health and climate safety for future generations.”
Ngā Kāinga Anamata has a firm focus on achieving the Government’s carbon emission targets, with significant benefits to occupants, and importantly, the people who live in these homes will enjoy a comfortable and healthy home without fuel poverty.
For more information on Ngā Kāinga Anamata, see