World’s smallest Passive House building?

What and where is the world’s smallest certified Passive House building? I was asked this question today and didn’t know the answer. It turns out my guess was way off.  Sustainable Engineering recently certified a New Zealand Passive House project that checks in at just 61.5m2 of Treated Floor Area (TFA). The question about the world’s smallest was asked by …

The right filter matters in your MVHR system

MVHR systems are great but they need the right filters and the right maintenance to do their job well. I draw your attention to a useful article published by Scottish ventilation consultancy and design service, Paul Heat Recovery. Filters remove various pollutants like dust, pollen, smoke and other particulates, making sure the air circulated inside buildings is clean and fresh. …

Thermal bypass a basic step to improving building performance

I get asked periodically how to increase building performance without spending extra money. Well, better-than-Code performance is going to cost something so I focus on low-hanging fruit: what’s the greatest benefit for the least cost? Let’s assume continuous mechanical ventilation is already included, because that’s the single most important thing. After that, I recommend preventing thermal bypass via a dedicated …

Keep heat pump and ventilation systems separate for best results

Buildings need fresh air, every single one of them. Even the very best-performing ones will also need some (possibly very little) heating or cooling at peak times of year. Ducting costs money and some people are tempted to combine heating/cooling systems with ventilation. Don’t do this, is my advice. Best practice is a fully decoupled system design for ventilation (dedicated …

SketchUp’s new release does not work with designPH 2.1

SketchUp 2024 is now available but if you are using designPH, please hold off on updating SketchUp until designPH2.2 is released! Otherwise you won’t be able to use designPH.  PHI has been working on this but SketchUp didn’t tell them it was releasing 2024 until it had already happened. PHI’s testing of designPH v2.1.15a found that the change to Ruby …

Is Passive House actually worth it?

I’m often asked (usually politely): Is building to the Passive House standard actually worth it? Yes it is, is the unequivocal answer. There’s a brilliant summary paper written by Dr Ürge-Vorsatz and others that is my go-to evidence when I am persuading sceptics. The bottom line is that with current technology, we can build nearly zero-energy buildings almost anywhere at …

Alternative balcony design for low carbon buildings

Global design practice Perkins & Wills has released a beautiful white paper on balconies for buildings concerned with lowering carbon emissions. It considers thermal bridges and overall design considerations. Balconies are a major heat loss junction in multi-storey buildings, second only to window installation details. (Concrete slab edges, where left uninsulated, are also major thermal bridges.) The white paper, according …

Build better houses to solve dry year energy problem

Newsflash: using less energy is better than generating more of it. I know that seems obvious given the cost of new electricity generation schemes but it’s even more significantly beneficial to reduce peak heating demand because of New Zealand’s big dry winter problem. The University of Otago’s energy programme is producing valuable work, and its latest paper by Michael Jack …

Revised ASHRAE standard gets serious on building decarbonisation

ASHRAE in the USA is really focusing on building decarbonisation, finally. ASHRAE Journal March 2024 contains a really readable summary of the changes to ASHRAE Standard 100-2024, Energy and Emissions Building Performance Standard for Existing Buildings. This amounts to a deep retrofit of the standard, which now will address both energy emissions (via Energy Use Intensity, EUI) and carbon emissions …