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How to Fireproof Your Next Home

Stewart Hansen CEO of EverLog Systems will present at the October 7th SC Works New Tech. His company has developed a new construction siding to make houses and structures fireproof. This article was contributed by EverLog Systems.

USING EVERLOG CONCRETE LOG PRODUCTS IN WILDFIRE PRONE AREAS

In 2003, over 4000 homes in the United States were destroyed by wildfires. And again this year (2014) wildfires in California and Arizona have already been particularly devastating. Our concrete log homes are non-combustible and have a minimum 3 hour fire rating. Not only do our concrete log homes provide superior fire protection, insurance companies provide our home owners with preferential insurance ratings resulting in lower homeowners insurance costs. Homeowners insurance is generally a minimum of 20% less costly than comparable frame or log homes. These savings increase in wildland urban interface areas.

A GUIDE TO FIREWISE PRINCIPALS

The Firewise Communities Program provides homeowners with simple and easy steps to help reduce a home’s wild fire risk by preparing ahead of a wildfire. These steps are rooted in principles based on solid fire science research into how homes ignite. The research comes from the world’s leading fire experts whose experiments, models and data collection are based on some of the country’s worst wildland fire disasters. Below are Firewise principles and tips that serve as a guide for residents.

When it comes to wildfire risk, it’s not a geographical location, but a set of conditions that determine the home’s ignition potential in any community.

Wildfire behavior is influenced by three main factors: topography (lie of the land), weather (wind speed, relative humidity and ambient temperature) and fuel (vegetation and man-made structures). In the event of extreme wildfire behavior, extreme weather conditions are normally present, like extended drought, high winds, low humidity and high temperatures, could with excess fuel build up including the accumulation of live and dead vegetation material. Additionally, the inherent lie of the land influences the intensity and spread a fire takes. Fires tend to move upslope, and the steeper the slope the faster it moves.

Of these three factors, fuel is the one we can influence.

Debris like dead leaves and pine needles left on decks, in the gutters and strewn across lawns can ignite from flying embers. Fire moving along the ground’s surface can “ladder” into shrubs and low hanging tree limbs to create longer flames and more heat. If your home has flammable features or vulnerable openings, it can also serve as fuel for the fire, and become part of a disastrous chain of ignitions to other surrounding homes and structures. 

When constructing, renovating, or adding to a Firewise home, consider the following:

  • Choose a Firewise location.

  • Design and build a Firewise structure with fire resistant materials.

  • Employ Firewise landscaping and maintenance.

To select a Firewise location, observe the following:

  • Slope of terrain; be sure to build on the most level portion of the land, since fire spreads more rapidly on even minor slopes.

  • Set your one-story structure at least 30 feet back from any ridge or cliff; increase distance if your home will be higher than one story.

In designing and building your Firewise structure, the primary goals are fuel and exposure reduction. Therefore:

  • Use construction materials that are fire-resistant or non-combustible whenever possible. All of EverLog™ Systems’ concrete log home products are fire-resistant and non-combustible.

  • For roof construction, consider using materials such as Class-A asphalt shingles, slate or clay tile, metal, cement and concrete products, or terra-cotta tiles. A fire-resistant sub-roof can also add protection.

  • On exterior wall facing, fire-resistive EverLogEverLog Siding, stucco or masonry may be much better choices than vinyl, which can soften and melt.

  • Window materials and size are important. Smaller panes hold up better in their frames than larger ones. Double pane glass and tempered glass are more reliable and effective heat barriers than single pane glass. Plastic skylights can melt.

  • Install non-flammable shutters on windows and skylights.

  • To prevent sparks from entering your home through vents,cover exterior attic and underfloor vents with wire screening no larger than 1/8-inch mesh.

  • Provide at least two ground-level doors for easy and safe exit, and at least two means of escape (i.e., doors or windows) in each room so that everyone has a way out. 

Any structures attached to the house, such as decks, porches, fences, and outbuildings should be considered part of the house. These structures can act as fuel bridges, particularly if constructed from flammable materials. EverLog Timbers can be used for deck posts & beams and since they are made from concrete they will not burn. Otherwise consider the following:

  • If you wish to attach an all-wood fence to your house, use masonry or metal as protective barriers between the fence and house.

  • Use metal when constructing a trellis and cover it with high-moisture, low flammability vegetation.

  • Prevent combustible materials and debris from accumulating beneath patio decks or elevated porches. Screen or box-in areas below patios and decks with wire screening no larger than 1/8-inch mesh.

  • Make sure an elevated wooden deck is not located at the top of a hill where it will be in direct line of a fire moving up-slope. Consider a terrace instead. 

A home’s ignition risk is determined by its immediate surroundings or its “home ignition zone” and the home’s construction materials.

According to fire science research and case studies, it’s not where a home is located that necessarily determines ignition risk, but the landscape around it, often referred to as the “Home ignition zone.” The home ignition zone is defined as the home and its immediate surrounds up to 200 feet. The Firewise Communities Program provides tips for reducing wildfire risk based on the home ignition zone concept: 

Zone One: 0 to 30 Feet (for all homes in the WUI)

Zone One is typically defined as 30 feet in all directions from your house and any attached structures such as decks, garages and storage buildings, as well as any trees next to the house you are incorporating into your defensible space. Experts recommend that everyone in the WUI create a Firewise Zone 1 regardless of your hazard-area rating.

Fire-Free Five. Make a minimum of the first five feet surrounding your house totally free of anything flammable. Use fire-resistant landscaping materials such as rock mulch (bark and chip mulch become flammable when dry) or stone walkways, or plant high moisture content annuals or perennials.

Five to 30 feet. Choose plants that are low growing and don’t contain waxes, resins and oils that burn easily. Group and space plantings so they don’t create a continuous path for the fire.

  • Trim tree branches that overhang the house.

  • Trim trees branches up 6 to 10 feet from the ground; this prevents the lower branches from serving as ladders for the fire to climb.

  • Space conifer trees so there is 30 feet between crowns. If you plan to cut down trees around your home to improve your defensible space choose wisely: conifers, pines, evergreens, firs and eucalyptus will catch on fire faster than hardwood trees.

  • Keep your grass watered and mowed. A well-watered lawn can serve as a fire break. A dry, overgrown lawn can serve as a fire path. If you live in an arid climate or have to deal with frequent water restrictions, consider landscaping with rock and fire-resistant, drought-tolerant plants and groundcovers.

  • Remove any dead vegetation from under decks and within ten feet of the house. Once you’ve screened in the space below your deck, you’ll have an easier time keeping blowing leaves and debris out. But it will probably still pile up when the wind blows, so make a habit of walking your perimeter regularly during fire season.

  • Locate propane tanks and woodpiles outside this zone.

Zone Two: 30 to 100 Feet (for Moderate and High Hazard Areas)

  • Use plantings that are low-growing, well-irrigated and less flammable.

  • Trees should be clustered in groups of two or three with 30 feet between clusters; leave 20 feet between individual trees.

  • Prune lower branches up 6 to 10 feet from the ground.

  • Encourage a mix of deciduous and coniferous trees if your climate permits.

  • Create fire breaks with walkways, lawns, water features, rock gardens, rock patios and gravel or paved driveways.

Zone Three: 100 to 200 Feet (for High Hazard Areas)

Reduce density in this area by thinning and creating more space between trees. Prune tall trees so the crowns (tops) don’t touch. Remove small conifers growing in between larger trees – they provide ladder fuel. 

If you have several acres or more, you might want to consult a forester about the smartest way to thin. Some studies show that thinning for thinning’s sake can actually make it easier for a surface fire to spread. The best approach is to execute a plan that takes typical fire behavior during dry and windy conditions into account rather than just thin to an arbitrary density.