Thermal bridge calc error rate is way too high

I estimate nearly half the thermal bridge calculations we see during pre-construction review are wrong. Newly minted Passive House designers and consultants are not wholly responsible. The Sustainable Engineering Ltd...

by Jason Quinn

Updated: Mar 2026

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Q&A: Is spray foam insulation a good idea?

Q. What’s your opinion about spray foam insulation for New Zealand homes? A. Spray foam can be used with good results if properly designed and installed well—but a successful outcome...

by Jason Quinn

Updated: Jul 2023

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MBIE releases technical guidance on operational carbon

I welcome the release of technical guidance for operational carbon calculations by MBIE, as part of its Building for Climate Change programme. There is lots of work ahead of us...

by Jason Quinn

Updated: Mar 2024

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Kids suffer when schools are poorly designed

Some solid work has been done in Aotearoa New Zealand by very capable architects and Passive House designers to design classrooms to Passive House performance levels. The fact none have...

by Jason Quinn

Updated: Mar 2026

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New thermal bridge requirements in US will influence NZ

There are new thermal bridging requirements being rolled out in the US, of which ASHRAE has just summarised. ASHRAE standard 90.1 is for all new buildings excepting low rise housing...

by Jason Quinn

Updated: Jun 2023

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Retrofitting wall insulation is not risk-free

This article from the BBC discusses claims cavity wall insulation installed as part of a government retrofit scheme has led to homes filled with black mould. The installer has gone...

by Jason Quinn

Updated: Mar 2026

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All homes need mechanical ventilation

I was happy to see this lovely article on a very high-performance home down in Greymouth but I take issue with the last sentence, which implies that mechanical ventilation is...

by Jason Quinn

Updated: Jun 2023

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Better building design improves sleep

Sleep is super important for good health and a good life. We know this but generally overlook how building design choices impact sleep quality.  An ASHRAE Journal article just published...

by Jason Quinn

Updated: Jun 2023

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Filtering out fine particulates increases life expectancy

Indoor air filtration capable of reducing PM2.5 particles increases life expectancy and experts argue should change standards to require better filtration. In general, the filters in ventilation equipment are primarily...

by Jason Quinn

Updated: Jun 2023

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Scotland sets example for new building performance

Commit to the outcome then work out how to get there, argues Andy Marlow, a leading Australian Passive House designer and former APHA board member. In a recent essay on...

by Jason Quinn

Updated: May 2023

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Australian homes aren’t warm either

Australia is much warmer than New Zealand but apparently not inside their homes in winter. This new study points out that 80% (!) of the Australian homes measured failed to...

by Jason Quinn

Updated: May 2023

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Economic benefits to extensive housing retrofits

Large-scale retrofit programmes to improve New Zealand housing would generate huge benefits, according to a recent report by BERL: $50 billion in health and energy savings and over $116 billion...

by Jason Quinn

Updated: May 2023

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Embodied carbon tools from NZ Green Building Council

The NZ Green Building Council undertook detailed consultation into what its clients needed to assess embodied carbon. It has released a suite of tools to assist with measuring, verifying and...

by Jason Quinn

Updated: Mar 2026

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Q&A with Jason: explain heating load vs demand

Q. What is the difference between heating demand and heating load and how is each measured? How do these numbers impact on Passive House certification? A. Both these numbers are...

by Jason Quinn

Updated: Jul 2023

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Your clients must own the risk that goes with cost-cutting

How is risk allocated in the design of new buildings? Who benefits and who pays for it? This is at the crux of some very interesting conversations I’ve been having...

by Jason Quinn

Updated: Apr 2023

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The slow switch to ISO standards in NZBC

New Zealand is slowly switching over to using ISO standards, at least for our building energy work and code in H1. The revised H1 switches to the following standards, so...

by Jason Quinn

Updated: Apr 2023

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Least cost, most benefit from jumping straight to Passive House performance

Something I learned from my dad growing up was to do something right … so you only had to do it once. When you do a half-arsed job, you often...

by Jason Quinn

Updated: Apr 2023

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Passive House in NZ: certification and rate of uptake rising

Sustainable Engineering is often asked how many PHI certified Passive House buildings there are in New Zealand. So a while back, we added a counter to our website here. We...

by Jason Quinn

Updated: Mar 2026

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