Menu

Ventilation of Wildfire Zones

Wildfires are no longer rare catastrophic events; they are a grim reality shaping the landscapes of countless communities. While much of the focus during and after wildfires is on their devastating outcomes, insufficient attention has been given to a silent but critical enabler of wildfire destruction: inadequate building codes that address the spread of embers into attics and other air spaces of the home.

The Invisible Path for Disaster: Vents

Wind-driven embers, which are the glowing fragments of burning material, are often the principal culprits igniting homes. These embers infiltrate through ventilation openings in attics, crawl spaces, and eaves. These unoccupied spaces being dry can quickly catch flame, along with the stored items often located in these spaces. Within a matter of minutes, the home could be ablaze.

While many newer buildings use ember-resistant exterior materials, older homes were not built to today’s standards. Many older homes still rely on outdated 1/4-inch mesh screens, which fail to stop embers. Modern fire-resistant venting materials and designs, such as those required by Chapter 7A of the California Building Code, feature fine mesh sizes between 1/16 and 1/8 inch and can significantly reduce ember entry, slowing the propagation of a fire leading to reduced loss of life and property. However, adopting these designs is inconsistent due to the lack of enforceable mandates across wildfire-prone regions.

Balancing Airflow with Fire Safety

One obstacle to broader adoption of improved ventilation solutions is the misconception that smaller meshes and fire-resistant vents reduce airflow too much. While this concern may have validity for older homes with archaic designs, the trade-off can be miniscule to the devastation that can occur. It is important to note, however, that the outdated models of older homes cannot be easily retrofitted with this new technology without some customization.  In newer homes these airflow restrictions are not significant, making for a much easier substation.

Why Codes Fall Short

Current building codes in many wildfire-prone areas prioritize conventional ventilation requirements and rodent-proofing over fire resilience. This oversight leaves older homes, and even some newer structures, vulnerable to ember attacks. The solution lies in harmonizing codes across regions to mandate wildfire-safe ventilation and incentivizing retrofits for older constructions.

We need leadership at both the community and governmental levels to recognize this gap. States like California, with their fire marshal-approved products, have created models worth replicating elsewhere. However, these products are still not enforced by codes, even in the state of California. Without these codes, wildfire-safe venting is only used when specified to the contactor.

Insurance companies can also be significant in code enforcement. Their lobbying for wildfire-safe venting solutions would encourage builders and manufacturers to find a solution to this devastating problem, like efforts that have been undertaken in hurricane-prone zones.

Solutions at Hand

Mandating Wildfire-Safe Ventilation: Codes should universally require the use of ember-resistant vents and smaller non-combustible meshes, ensuring that fire resilience becomes the norm rather than the exception.

Public Education: Homeowners need clear guidance on the impact venting has on wildfire progression. Educational campaigns could help remove the stigma of upfront costs by emphasizing long-term resilience.

The Cost of Complacency

Ignoring ventilation codes is no longer a passive choice—it’s an active decision to risk lives and property. The science is clear: wind-driven embers are avoidable intruders when buildings are adequately ventilated with wildfire safety in mind.  While no home can ever be made completely fire-proof, designs and technology exist today that can significantly slow the spread, giving homeowners a chance to safely evacuate and firefighters a chance to more quickly extinguish these deadly wildfires.

It’s time for regulators, builders, and homeowners to work together to close the ventilation gap before more neighborhoods find themselves erased in the face of preventable disaster.

To Read More About Venting Risks in Wildfire:

https://up.codes/viewer/california/ca-building-code-2016/chapter/7A/sfm-materials-and-construction-methods-for-exterior-wildfire-exposure#706A

Fire-Resistant Vents

Wildfire Venting Products:

Home – Brandguard
Vulcan Vents

Bulk Discounts + Free Shipping = Pro's Advantage | Learn More
Bulk Discounts + Free Shipping = Pro's Advantage
Learn More