Passive House Design: Mild Temperate - Andy Marlow, Envirotecture

How do you design a Passive House in a mild temperate climate like Melbourne?

In today's episode, I continue to investigate the design specifics for each of the four climate zones around Australia where most of our population lives. I talk to very experienced Passive House designer Andy Marlow, a director of the award winning environmental practice Envirotecture in Victoria and New South Wales.

In this episode, Andy explains the Passive House design specifics for Mild Temperate. Plus we talk more about Enerfit, the renovation and retrofit tool, and he shares heaps of other information and insights from his years of experience to help you better understand Passive House.

Australian Architects can claim formal CPD hours for these podcasts.

MORE INFORMATION

Find everything you need on the Renovation Collaborative website.

www.renovationcollaborative.com.au

• PODCAST Key points summary, timestamps and resource links
• FREE RESOURCES Transcript edited into clear Q&A.
• CPD Australian architects can find more information on CPD, and
• COURSES Eleven easy to read courses demystifying the entire home design and construction process.

KEY POINT SUMMARY

1. In terms of the five Passive House design components, mild temperate is very similar to cool temperate.

• Windows are double or sometimes triple glazed depending on the design.
• The fresh air circulation system is an HRV
• Stud framed wall thicknesses are typically 140mm to allow for more insulation, and insulation is required to separate a concrete floor slab from the cool earth temperature below.
• An internal wrap for air tightness and moisture control is usually required in addition to the exterior weather tight wrap, and
• Removing thermal bridges is always important.

2. The colour of the roof and walls is considered in the PHPP modelling and affects the design's performance. In cooler climates, dark coloured buildings perform slightly better than light coloured buildings. Dark coloured roof and walls will dry out faster which can be beneficial to reduce any moisture in the wall and roof structure. However, Andy noted that as a nation going forward into climate change and increasing temperatures, generally speaking, lighter coloured buildings are the best solution.

3. Passive House is a performance standard so buildings can be constructed from any material as long as they deliver the required results through the PHPP modelling. Andy references a Passive House that Envirotecture have completed made from straw bale.

4. Passive House certification costs around 3 to 8% extra, however the value it adds far outweighs the extra cost. Envirotecture prefer to build certified Passive Houses over uncertified high performance because of the rigorous testing on site. The quality assurance.

5. When renovating, the whole building must be upgraded to achieve Enerfit certification. Improvements must be made to...