Increasingly, due to the warming climate, wildfires are becoming more common than in the recent past, posing a threat to towns and rural development. Part of the reason has to do with how wildfires burn.
Embers spread by high winds can enter communities and set structures on fire. For instance, the fires that led to the home losses in Pacific Palisades and Altadena, California, this past winter were wind-driven events. High winds propel all large fires.
The government’s focus on forest thinning and prescribed burns leads to a misallocation of funds. Reducing home flammability is far more cost-effective than trying to fire-proof a forest. Not to mention, more than half of the wildfire acreage occurs in scrublands and grasslands.
How and where we build can determine how vulnerable homes are to wildfires. If a house is fire-resistant, it can withstand a blaze. One can do things like removing litter from gutters, installing sprinklers on roofs, screening vents, and other home-hardening practices to reduce the flammability of the home.
However, the fact that the majority of all homes in the Western US are now constructed of wood increases their vulnerability to wildfire. If you travel through the western US, you often find that the older buildings in the oldest parts of the communities were constructed of brick. Most of the older buildings in downtown Livingston, Montana, where I own a home, are built of brick.
Back at the turn of the century, water bucket brigades were the only way to douse a fire. Brick buildings were less likely to burn. The American Society of Civil Engineers highlights that brick construction reduces the risk of fire damage by 90%.
Today, however, most homes are constructed from wood. Interior wood inside a home ignites at a temperature of approximately 1000 degrees. One of the interesting observations one sees frequently in urban fires is the complete destruction of the house while nearby trees and shrubs are still green and standing.
That is because most urban vegetation is watered, and the interior moisture resists ignition. In contrast, kiln-dried lumber that makes up most home construction has much less internal moisture, hence burns more readily than surrounding suburban vegetation.
Some construction advocates suggest using steel framing and cement fiber board siding to resist wildfire. It takes 2500 degrees to melt steel. Thus, a steel-framed home is likely to withstand wildfire. While typical steel framing may cost 10-20% more than wood, metal framing lasts much longer. Moreover, if your home survives a fire due to non-wood construction, it is far less expensive.
In addition to the fire vulnerability of wood, home construction is the preponderance of oil-based plastics and other materials common in modern homes that are highly flammable. One study found it took approximately 30 minutes for a fire to consume a room furnished with furniture and fixtures typical of fifty years ago. Today, with modern synthetic products, the same room is entirely engulfed in flames in three minutes.
The change in fire spread found in modern homes raises safety issues as well. Fifty years ago, you would have 8 minutes to evacuate a burning room, while today you have two minutes.
Given that climate warming is likely to continue into the future, rethinking home construction materials might be advisable.
The post Home Construction Materials Can Increase Losses to Wildfires appeared first on CounterPunch.org.
This content originally appeared on CounterPunch.org and was authored by George Wuerthner.