'Passive house' survives fire in California

by tehnubon 1/16/2025, 4:22 AMwith 62 comments

by turtlebitson 1/16/2025, 5:43 AM

This is not a passive house, this was confirmed by a builder on Youtube who contacted the architect.

The features called out that contributed were - Stucco siding - Metal roof with no overhangs - ~4' tall concrete wall - 1 hour fire rated exterior wall assembly

by pamelafoxon 1/16/2025, 4:54 AM

For folks in the east bay area, the Berkeley fire department gave a great talk on fire risk reduction: https://www.youtube.com/watch?v=0MUh16czYGk&t=239

In the past year, I’ve added gutter guards, removed trees in zone zero (especially fire-prone cypress), and hardscaped zone zero. I need to look into whether we can do more sealing like this passive house- bit tricky with 1950s construction.

by larussoon 1/16/2025, 5:17 AM

Reminds me of my home here in Germany. I guess it’s not as sophisticated as the architects where more concerned with energy savings then fresh air. Means in the early years we had to vent the house manually a lot. I friend of mine renovated his house and installed on top an automated air refresh system. I wish my house had the same.

What I mean specifically is that around 2010ish the energy footprint started to be become more and more important. Currently the building codes here are so crazy that building a new house demands quite the upfront costs.

by Full_Clarkon 1/16/2025, 6:15 AM

I'd love to know more about the windows. The architect's thread on Twitter mentioned that the windows are made of tempered glass, but I don't know if that's significant because they withstood impact damage better, or rejected heat better, or for some other reason.

Often there are flammable interior furnishings close to windows in a home (e.g. fairly flimsy cloth curtains). I wonder if the radiant heat of a nearby structure or vehicle fire is sufficient to ignite them through a typical residential single-paned window. In other words, is there a fire danger even when the window pane doesn't break and embers or hot gases stay on the outside?

by adrianNon 1/16/2025, 5:01 AM

> Though still a fairly new trend on the market

Passive Houses are a thing since the seventies or so and fairly common since the nineties. Does that still count as a "new trend" in real estate?

by hackeraccounton 1/16/2025, 1:45 PM

I've head that fire resistance and earthquake resistance work against each other. That the things that make a house fire resistant - stucco/metal roofs - are bad for earthquakes and the things that make earthquake resistance - flexibility - are bad for fire resistance.

Reading just a bit it seems like the question is how you get that flexibility; the easy way would seem to be building with wood which is tricky with fires.

Any truth to this?

by nielsboton 1/16/2025, 5:22 AM

Reminds me of this story about this hurricane-resistant house left standing in Mexico Beach, FL after Hurricane Michael:

https://www.nytimes.com/2018/10/14/us/hurricane-michael-flor...

by willsmith72on 1/16/2025, 5:04 AM

How does an airtight house work day-to-day? If I don't open a window, how quickly am I poisoning myself?

Not knocking the idea, I've heard of them before and experienced the joy of triple pane glass (both in insulation and noise protection)

by iosguyryanon 1/16/2025, 5:40 AM

Do you turn the HRV off during a wildfire to stop smoke intrusion from destroying the house?

by userbinatoron 1/16/2025, 4:54 AM

I'm curious what temperature its contents reached.

by fnord77on 1/16/2025, 6:01 AM

couldn't houses be clad with something like Space Shuttle heat tiles?

by KevinMSon 1/16/2025, 5:16 AM

weren't these called "superinsulated" just a few weeks ago?

by chmod775on 1/16/2025, 4:54 AM

"other construction material more fire resistant than plywood box held together by spit and prayer"

How interesting.

In all seriousness you could make a home from almost anything else and it would end up being more fire resistant. The flammability of your average US suburb has to rank somewhere near 1944 Tokyo.

by sebmellenon 1/16/2025, 5:04 AM

One thing I'm curious about is how the CO2 levels in these "passive houses" look. If there's limited indoor to outdoor air exchange, wouldn't they build up? Is there a scrubbing mechanism?

by Shankon 1/16/2025, 5:06 AM

Of course, if you build a house with a tight envelope and reduce air circulation, you can easily have poor indoor air quality. You still need a strategy for this, and in my opinion, it’s very overlooked.

https://www.researchgate.net/publication/273588438_Building_...