Sustainable House Day - 2024

Another successful Sustianable House Day. It was all quite civilised with 46 people across three sessions. Lots of great questions and interested people.

Popular posts from this blog

Temperature (Out vs. Old vs. New)

Image
I have fielded more than a few questions about the temperature of our passive house versus the temperature of the house that we lived in prior (on the same lot).  So I've used the data I had on hand which is temperature (°C) recorded every 5 minutes over since October 2012. For the sake of consistency I am only using the NetAtmo sensors that I have had for that entire period. So I only have one outside sensor and one inside sensor located in the the respective living room. The outside sensor moved around a bit, but it should be good enough.  I've converted those measurements to hourly averages.  This ends up being ~ 66,955 hours to play with (52,232 hours from the original house, 14,723 hours from the passive house). I've left the rental house out of this comparison, but it was disturbing like the original house despite being ~ 20 years old. The key take-home messages: The passive house a much less variation in temperature than the original house (or outside).  ...
Read more

Five year retrospective

Image
Every so often I find myself chatting with someone about the performance of the house and I am caught out with not actually having looked at the numbers except on a month-by-month basis. So here is a bit of a look at 5 years of data. March 2020 - February 2025. Hard to believe that we have been living here for over 5 years, but we have been (actually longer than that, but the data are consistent back to mid-February 2020). For the record, I am using data spanning the 1st of March 2020 through 28th of February 2025. A few things of note. In winter months, we aim for a house temperature at or above 18 °C inline with the WHO recommendations and a general happiness with sleeping / waking up to a house that is ~ 18 °C. Using the hourly averages, the outside temperature ranged from 0.2 to 42.4 °C with a median temperature of 17.1 °C. The inside temperature ranged from 17.6 to 26.6 °C with a median temperature of 22.2 °C. Over the past 5 years, we have been in the passivhaus temperature t...
Read more

H/ERV in the Sydney climate...

I should preface this post by saying that I am not the kind of person who likes to wear a jumper in the house during the middle of summer or shorts inside the house during the middle of winter. I get that the Passivhaus standard is all about specific temperature (20 - 25 °C) and specific humidity levels (not measured as relative humidity), but to me 18 °C feels great when you walk in from 8 °C and 27 °C is blessedly cool when it is 40 °C outside. By which I mean to say that as a biologist I undertand that the we experience things relative to our frame of reference, but I also like data. So over the past 12 months we have had a few bits and pieces on loan from Zehnder and FanTech to see if ERV or HRV are better in the Sydney climate. I've learned alot in the process... and as I understand it none of this is commercial in confidence - quite to the contrary they are pleased for people to know about how their products work in Sydney. Spoiler: It works really well and I would absolu...
Read more