‘Passive house’ survives California fire
The latest stats out of California project that over 40,000 acres have been scorched as of Jan. 14. The initial blaze in Pacific Palisades stands at 17% containment, with nearly 24,000 acres decimated.
A week after the fires started, winds were predicted to return with a force, which “could cause extreme fire behavior in the blazes or turn any new spark into a raging inferno,” according to CNN.
Greg Chasen’s house in Pacific Palisades, which he built in 2024, still stands while the neighboring homes burned down. The house on Iliff Street is the “single one” that “remains intact,” Mansion Global reported.
“If it weren’t for several fire-resilient design strategies, the home would have been destroyed,” Bloomberg reported.
How a passive house is built
To qualify officially as a passive house, a home must meet certain criteria set by the International Passive House Association. The dwelling must consume 86% less energy for heating and 46% less for cooling compared with other code-compliant buildings in the same climate.
To reduce or even eliminate the need for heat in the winter and air conditioning in the summer, a passive house is built airtight, using strong exterior insulation, triple-pane windows, and construction methods that ensure no heat is transferred across the exterior of the building. No outdoor air seeps in, and no indoor air escapes.
This airtight construction is one of the reasons the house could withstand a blaze.
What are the passive house principles?
While nothing is entirely fireproof, there are several ways to protect a house.
- Superinsulated envelopes
- Airtight construction
- High-performance glazing
- Thermal-bridge-free detailing
- Heat recovery ventilation
Zachary Semke, director at Passive House Accelerator, tells Realtor.com that many essential principles of passive house design help make buildings resilient to fire and smoke.
“Airtight construction helps stop embers from being sucked into building envelopes,” says Semke. “Simpler forms (fewer zigs and zags, bump-outs, etc.) mean fewer nooks and crannies for embers to take hold, plus less overall surface area exposed to fire risk.”
Stay up to date with the NYP’s coverage of the terrifying LA-area fires
Passive house cost
States such as New York, Massachusetts, and Pennsylvania have been early adopters of passive houses. As of 2023, “16,000 units of Passive House multifamily housing (apartments or townhomes) were built or are in the process of construction nationwide,” according to the Passive House Network.
There are currently 12 million square feet of passive house-certified buildings in the U.S., according to Semke. They’re a combination of single-family and multifamily buildings. Those projects are certified by one of two independent certifying bodies: Phius (based in Chicago) and Passive House Institute (based in Darmstadt, Germany).
Yet, one of the most significant drawbacks of these structures is their up-front costs.
According to Semke, these single-family homes are typically 5% to 10% more expensive when designed with cost optimization in mind. However, the upfront investment brings ongoing savings in utility bills.
Conclusion
In conclusion, the “passive house” that survived the LA fires is a testament to the benefits of fire-resistant design. The airtight construction, fire-proofing features, and attention to detail all contributed to its survival. As the world grapples with the increasing threat of wildfires, these principles can serve as a valuable lesson in building resilience and sustainability.
FAQs
Q: What is a passive house?
A: A passive house is a type of building that is designed to be extremely energy-efficient and environmentally friendly, using principles such as airtight construction, superinsulation, and high-performance glazing.
Q: What are the benefits of a passive house?
A: A passive house can reduce energy consumption by up to 86% for heating and 46% for cooling, and can also improve indoor air quality and reduce noise pollution.
Q: Is a passive house fireproof?
A: While nothing is entirely fireproof, passive houses can be designed with fire-resistant materials and features, such as metal roofs and fire-resistant underlayments, to increase the chances of survival in a fire.
Q: Are passive houses more expensive to build?
A: Yes, passive houses can be 5-10% more expensive to build than traditional houses, but the upfront investment can lead to significant long-term savings on energy bills and reduced maintenance costs.
