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From Colorado’s grasslands to its mountains, nearly every part of the state is vulnerable to wildfires. In the wildland-urban interface, those areas where wildland fuels coexist with human development, fires catch and burn easily. So, if you live in or near Colorado, fireproofing your home needs to be a top priority. James Hardie siding products can help keep your home safe. Here’s how it works.

Degrees of Flame-Spread

It might seem that your home is either fireproof or it isn’t. But the truth is far less clear cut than that. Actually, there are degrees of fireproofing. In other words, your home may be more or less safe from fires, but not necessarily completely safe or unsafe. One key factor is the degree of flame spread.

The degrees of flame-spread are identified using a I-II-III or an A-B-C classification system. The two systems are equivalent. For building materials, the designations are:

  • Class A or I – Flame-spread index of 25 or less
  • Class B or II – Flame-spread index of 26-75
  • Class C or III – Flame-spread index of 76-200

The main thing to remember about these systems is that Class A or I materials are the safest, while Class C or III allows flames to spread the most and the fastest.

Hourly Ratings

Hourly ratings have been developed to test building materials for combustibility. The time factor is how long the building material can withstand heat from a fire without allowing the structure to catch fire. Remember that what matters in these ratings is not whether the surface ignites but whether the surface gets so hot that it conducts enough heat to ignite the materials on the other side of it.

How James Hardie Siding Products Stack Up

James Hardie fiber cement siding panels are considered masonry products. So, they have all the same attributes as stone, brick, and stucco, including fire-resistance. Flame-spread is not a problem with James Hardie siding, because it’s made primarily of cement. As for flame-spread, James Hardie siding has an index of 0, meaning that it won’t allow the fire to spread directly.

However, the heat can conduct to the interior. That’s why it’s important to combine the siding with a fire-resistant wall assembly. When you do that, the hourly rating of James Hardie siding can achieve a 1-hour rating.

James Hardie’s Wall Assembly

James Hardie siding can be combined with their HardieWrap weather barrier and rigid foam insulation to create an exterior wall system that holds up to heat even better. It not only doesn’t catch fire, but it also doesn’t transfer the heat easily to the interior materials. In this assembly, James Hardie siding is flame resistant and non-combustible. Compare this to vinyl siding, which melts and burns easily.

Adequately fireproofing your home is not an easy matter to understand. That’s why it makes sense to consult with a Colorado-area exteriors expert when deciding which products are best for siding your home. To learn more, contact GS Exterior Experts by calling (720) 683-6288 or using our convenient Contact Us form. We are a Colorado home improvement company dedicated to bringing you the best in home construction products and installations.

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