Wildfires and Home Design: Structure and Safe Room

The first aspect of your home that can be enhanced to provide greater protection against fire is the structure. The materials that make up the walls of your home have an enormous effect on the potential for your home to sustain a wildfire. There are a couple alternatives to wood-framed construction that can significantly increase your home’s chance of withstanding the danger of fire. Autoclaved Aerated Concrete Blocks, which provide an hour of fire protection per square inch, are blocks made of concrete and aluminum, but are half the weight of standard concrete blocks and come in manageable widths. A video on the blocks can be found here!  Another option are walls made from Insulated Concrete Forms (ICFs) that can withstand flames for about three hours.  ICFs are ultimately molds filled with 4 to 6 inches of concrete. Unlike wood and steel, concrete does not burn, soften or bend. It takes thousands of degrees Fahrenheit for concrete to start to break down, which means ICFs are a solid (no pun intended) choice for the structure of your home. 

If you decide to go with the popular wood framed house, there are still insulation options that allow your house better protection. Not only will the type of insulation affect the fire resistance of the house, but it will help your house stay cool during the summer and warmer in the winter. One type of insulation that does wonders when protecting from fire is mineral wool insulation that can withstand heat up to 1,800 degrees F.  Cellulose insulation is known to withstand temperatures up to 1,200 degrees F and can be a defense against burning.

Have you ever thought about designing a safe room into your home? A safe room, usually used in tornado and hurricane prone areas, is a hardened structure that provides "near-absolute protection" in extreme weather events. Although FEMA designates these structures for tornado and hurricane areas, they can also protect belongings during a wildfire, with some of the structures having a four hour fire rating. The safe rooms can be placed anywhere within the house and are constructed out of an insulated concrete ceiling, an insulated steel door with multiple deadbolts, and a cast in place steel frame. The room can be as large or as small as you wish and can incorporate “normal” interior finishes. In homes, these rooms can protect personal belongings from theft and fires.

Watch for our next post about how to cover these fire resistant structures with cladding and roofs.