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 …
Simple timber buildings are ripe for retrofits
This Canadian retrofit project is encouraging: it’s an old timber-framed and clad building with single-paned glazing in timber frames. Built in the 1850s, it’s older than the New Zealand homes built from the same materials. Regardless, it’s this kind of construction that offers the best retrofit potential in New Zealand—even better if they are two-storey like this Nova Scotian example. …
10 Passive House design tips for keeping cool in summer
The high temperatures this past summer have served to sharpen everyone’s focus on how to design Passive House buildings to remain comfortable for longer when the temps spike. The team at Sustainable Engineering Ltd is working on detailed energy modelling in order to produce building specification guidelines. We’ve also been thinking about what could be implemented right away: finding the …
Siddall’s latest paper does not say Passive House homes shouldn’t use recirculating kitchen extraction
Mark Siddall is a Passive House pioneer in the UK and his latest (collaborative) paper is of course worth reading. It reviews the indoor air quality (IAQ) in residential Passive House dwellings and it contains lots of good news. It confirms much of what drives us to design MVHR (ventilation) systems well in high-performance buildings. Much of the immediate discussion …
Fine particulate pollution is terrible for human health
Today I learned that lymph nodes are heavily impacted by air pollution. This photo shows lymph nodes specifically associated with the lungs and how they are affected by air pollution as we age. It’s gruesome. I already knew fine particulates were bad, but this image has visceral impact and I’ll strengthen the advice I give to clients about how to …
Design Passive House for your individual client
Should Passive House designers be doing more to design buildings that avoid summer overheating? This article from mainstream business magazine Forbes considers Bahnstadt, a Passive House district in Heidelberg, Germany. The story quotes residents who were struggling to stay comfortable as summer temps soared in 2023. The two residents have different motivations for living there and different experiences of their …
Lee home in Cockle Bay is outstanding but it’s not a certified Passive House yet
The Lee family home in Auckland—all 660m2 of it—is indeed newsworthy but it is unfortunate that Stuff has twice jumped the gun (here and here) by describing it as a certified Passive House building. It isn’t, yet. Sustainable Engineering Ltd is the Passive House certifier on this project and we’re not aware of any road blocks to it achieving its …
Morning Report: why are NZ homes so damn hot right now?
Morning Report rang me this week for comment about overheating homes, in the face of record temperature spikes. You can listen to the short segment here, or there’s a print version also. For the physics geeks, here is how I worked out the numbers I provided about emissions. I used an average grid emissions factor of 0.12 kgCO2e per kWh …
New free tool for exploring climate files
I’ve discovered a climate file exploration tool that will be really useful for Passive House designers. Best, it’s open source, so free to use. This is particularly timely given the promised update to the climate files we currently use for Passive House design in Aotearoa. What we currently access contains 30 years of climate data—but NIWA compiled those files 20 …