Posted by Mark J. Platten, Teller County Extension Director
As
my cohort, Sherie Caffey, spoke about in a recent blog article, now is a good
time for pruning and trimming trees for most species. This is especially true
if you are one of the many Coloradans who live in the wildland-urban interface
(WUI – pronounced woo-eee). The WUI is any area where structures and other human
developments meet or intermingle with wildland vegetative fuels. In many
vegetation types, it is not a matter of if a wildfire will impact
your home, but when.
 |
| Forest Fire photo by Skeeze |
Defensible Space
For
those of you who live in this zone, you’ve probably heard the term “defensible
space” thrown around at an emergency management meeting or even a training put
on by the various fire departments or natural resource agencies across the
state. A misnomer is that if a homeowner creates a defensible space around
their property, it will survive a wildfire. In truth, when fires like the 2002
Hayman, 2012 Waldo Canyon, or 2013 Black Forest fires occurred in my area, they
were so massive, with winds pushing embers more than a half mile from the fire
front, that it is not fair to say any home in the direct path of those fires
were “defensible,” not if we value human life over our homes.
 |
| Photo by Skeeze |
The
term does mean is that we can give ourselves a better shot at having our home
survive a wildfire and if it is safe for the firefighters to get their vehicles
in and back out of your property, they may be able to help protect your
structures. If enough of your neighbors, communities, and local/state/federal
lands around you are mitigated in a defensible space format, it will likely
help slow a wildfire’s advance.
So,
while you’re sitting at home because of the recent winter storm (at least
that’s what I’m doing) you may want to think about the following steps in
providing defensible space around your home and some additional steps in making
sure your home isn’t a tinderbox for embers.
Defensible Space Zones
Zone 1
The width of Zone 1 extends a
minimum distance of 15-30 feet outward from a structure, depending on property
size. Most flammable vegetation is removed in this zone, with the possible
exception of a few low-growing shrubs or fire-resistant plants. Avoid
landscaping with common ground junipers, which are highly flammable.
Zone 2
Defensible Space Diagram
An area of fuels reduction designed
to diminish the intensity of a fire approaching your home. The width of Zone 2
depends on the slope of the ground where the structure is built. Typically, the
defensible space in Zone 2 should extend at least 100 feet from all structures.
If this distance stretches beyond your property lines, try to work with the
adjoining property owners to complete an appropriate defensible space.
Zone 3
Has no specified width. It should
provide a gradual transition from Zone 2 to areas farther from the home that
have other forest management objectives. Your local Colorado State Forest
Service forester can help you with this zone. This zone provides an opportunity
for you to improve the health of the forest through proper management.
The Home Ignition Zone
Two factors have emerged as the primary determinants of a home’s ability to survive a wildfire – the quality of the defensible space and a structure’s ignitability. Together, these two factors create a concept called the Home Ignition Zone (HIZ), which includes the structure and the space immediately surrounding the structure. To protect a home from wildfire, the primary goal is to reduce or eliminate fuels and ignition sources within the HIZ.
Roof
The
roof has a significant impact on a structure’s ignitability because of its
extensive surface area. When your roof needs significant repairs or
replacement, use only fire-resistant roofing materials. Also, check with your
county building department – some counties now have restrictions against using
wood shingles for roof replacement or require specific classifications of
roofing material. Wood and shake-shingle roofs are discouraged because they are
highly flammable and are prohibited in some areas of the state. Asphalt
shingles, metal sheets and shingles, tile, clay tile, concrete and slate
shingles are all recommended roofing materials.
Roof Eave and Soffits
 |
| Soffit Example |
The
extension of the roof beyond the exterior structure wall is the eave. This
architectural feature is
particularly prone to ignition. As fire approaches the
building, the exterior wall deflects hot air and gasses up into the eave which
is usually cased in a soffit. If the exterior wall isn’t ignition-resistant,
this effect is amplified.
The
soffit is the skin that covers your eaves — without it, you would see your
rafter beams fully exposed. Functionally speaking, soffit protects your rafters
from the weather elements. Also, soffit helps your building breathe. With vented soffit, air can flow through the
vents to provide regular air circulation to your attic. This venting is where
the embers can be carried into the attic and burn the home from the inside out.
You’ll want to make sure your soffits are rated for the heat a wildfire could
bring and that any vents are covered with 1/16 steel mesh to prevent embers
from being pulled into your home.
Decks
 |
| Home burning photo by Mark Thiessen |
Most
decks are highly combustible. Their shape traps hot gasses, making them the
ultimate heat traps. Conventional wooden decks are so combustible that when a
wildfire approaches, the deck often ignites before the fire reaches the house.
This mostly happens because the decks are open beneath and dried leaves, twigs,
grass, and other tinder items are contained there so when an ember gets blown
under the deck, it combusts. Again, 1/16 metal screening placed around your
deck after you clean out all the debris, woodrats, skunks, cats, and
neighborhood children, is the best protection from embers.
Windows
Windows
are one of the weakest parts of a building with regard to wildfire. They
usually fail before the building ignites, providing a direct path for flames
and airborne embers to reach the building’s interior. Don’t plant shrubs
directly below your windows or they could contribute to the windows failing.
Gutters/Chimney/Dryer vents/Stucco gaps
 |
| Photo by KRCR News |
All
these areas are where embers can either ignite or be brought into your
home. Make sure your gutters are clean
and even better would be to install gutter guards to prevent buildup of
needles, leaves and other debris. The chimney should have an ember arrester on
it to prevent you from starting
Finally, a vigilant homeowner who has taken to the steps to build a
stucco home for fire protection will want to seal the gap on the outside bottom
of the home where the stucco often ends just before meeting the ground. There
is a gap of ½-1 inch that is often filled with steel wool to prevent mice from
getting in but guess what happens when embers meet steel wool…fire.
a forest fire. An often overlooked item is your
dryer vent that could be a vector for embers. |
| Photo by Mark J. Platten |
So,
while you’re watching the snowflakes swirl around you, take a break and head
outside to do an
inventory of possible issues on both your landscape and home. Then make sure to mitigate those issues to help your home survive the next wildfire.
Additional
resources and links can be found here: https://extension.colostate.edu/disaster-web-sites/fire-resources/#land
No comments:
Post a Comment