Homes with ember resistant vents have a reduced risk of ember intrusion. This article explains two ember-resistant vent options that homeowners can install today.
Contact Total Screen for a free on-site estimate for our ember screen installation services.
Homeowners across the western United States are increasingly aware that the greatest wildfire threat often comes from embers, rather than towering flames.
The biggest thing that causes these homes to burn is ember intrusion… You’ve got hurricane-force winds pushing embers toward houses.
Chip Prather – Fire Chief, Orange County Fire Authority
During wildfire events, an ember storm can send tens of millions of embers into the air, and those embers can travel on the air for a mile, or farther.
Exterior vents on a home are a major wildfire vulnerability, since embers can enter a home through vents and start a fire inside your attic or crawl space.
One of the most effective ways to reduce your risk of ember danger is to upgrade your home's exterior vents, either with an ember-resistant vent screen, or a retrofit ember-resistant vent.
This article explains the idea behind ember-resistant vents, why they’re essential for home hardening against wildfire damages, and we'll explain the two main approaches homeowners can take.
Ember-Resistant Vent Retrofits
or
Ember-Resistant Vent Screens
We’ll also link to additional resources on how far fire embers travel, screening your under-eave vents with DIY screen installation techniques, plus this article we wrote about California's 7A building-code requirement, so you can dig deeper on any topic that interests you.
2 Out Of 3 Homes Burned from Embers in Rancho Bernardo 2007
What Are Ember-Resistant Vents?
Every home needs vents to control moisture and heat in the attic and crawlspace.
Standard vents, however, typically rely on ¼-inch mesh, which is meant to keep out rodents rather than embers.
Wildfire-preparedness guidance points out that: “common ¼-inch screens are ineffective” and advises homeowners to “cover all existing vent openings with ⅛-inch or 1⁄16-inch wire mesh; do not use fiberglass or plastic mesh because they can melt and burn” and to “protect vents in eaves or cornices with baffles to block embers, backed by 1⁄16-inch wire mesh” [1].
California’s Chapter 7A further requires that vents “shall resist the intrusion of embers and flames” and must be protected by a “corrosion-resistant and noncombustible wire mesh screen with 1⁄16- to 1⁄8-inch openings” [2].
Ember-resistant vents are purpose-built openings designed to meet these criteria and stop wind-blown embers while still allowing airflow.
Commercially available ember-resistant vents use a variety of design elements to block embers.
Fire-resistant manufacturers combine fine metal mesh with baffles, louvers or honeycomb matrices, and many include intumescent coatings that swell and seal the vent when heated [4][5].
These design elements satisfy the requirements of Chapter 7A and create a barrier that resists ember and flame intrusion.
Why Ember-Resistant Vents Matter
During a wildfire, embers are inevitable.
NIST emphasizes that “embers can travel miles ahead of a wildfire and ignite spot fires ahead of the flaming front” and warns that embers can ignite structures and other parcel-level features even hours after the flame front has passed [3].
The U.S. Fire Administration echoes this, noting that embers can be “carried by winds and deposited several miles downwind” and that “millions of them…could impact a structure” during a single event [4].
These embers may smolder silently inside a home for hours before visible flames appear, underscoring the importance of stopping them at entry points [4].
If you’re curious about the science behind ember travel and ignition, this article by Total Screen provides an in-depth answer to the question 'how far can fire embers travel?'
If you’re curious about the science behind ember travel and ignition, this article by Total Screen provides an in-depth answer to the question 'how far can fire embers travel?'
Your Ember-Defense Options
Homeowners have two primary routes to achieve ember-resistant ventilation: replace existing vents with specialized ember-resistant models, or attach stainless-steel mesh screens over existing vent openings.
1. Ember Resistant Vent Retrofits
Retrofit vents are engineered vent products which replace your existing vent assembly, often by removing the old vent, and retrofitting it a new ember-resistant vent.
In the USA, there are several brands of ember resistant vent that a homeowner can install on their home:
Vulcan Vents use metal-mesh screens on the front & back, plus a honeycomb matrix of intumescent material that swells up when exposed to heat.
Brandguard Vents employ a baffle design to deviate the path of incoming embers, cooling them and trapping them before they can get inside.
Embers Out vents incorporate multiple internal layers of louvers to block embers [5].
An additional benefit to some retrofit vent products, like Brandguard vents, is that they can be custom-painted to match your home’s exterior.
Each of these ember resistant vent retrofits are built from metal materials, and some are coated with special fire-safety materials; these retrofit vents all meet California’s Chapter 7A and ASTM testing standards and provide a high level of ember and flame resistance [2][5].
Installing retrofit vents usually requires removing the original vent and modifying the surrounding soffit or wall to fit the new unit.
Ember-resistant vent installation may require a contractor, especially for roof or gable vents at height.
Benefits to Ember-Resistant Vent Retrofits:
- Meets or exceeds Chapter 7A standards for ember and flame resistance.
- Integrated baffles and intumescent materials offer superior protection from ember intrusion.
- Can be custom-painted to blend with your home.
For a deeper dive into Chapter 7A requirements and approved vent designs, read Total Screen’s California Building Code Chapter 7A – Explained.
2. Ember Resistant Vent Screens – The Accessible Alternative
For many homeowners, adding an ember resistant vent screen over existing vents is the simplest, and most cost-effective, solution.
Ember resistant vent screens are designed for simple installation; ember screens are installed directly over a home's exterior vents.
California's state guidance recommends using 1⁄16- to ⅛-inch non-combustible metal mesh because “¼-inch screens are ineffective” and larger openings can allow embers to slip through [1][2].
At Total Screen, we offer “Ember Screens” made from black, powder-coated stainless steel mesh that meets Chapter 7A requirements.
Total Screen's ember screens can be installed on any size of home vent, and they virtually dissapear when installed, since the black, powder-coated mesh creates the apperaance of a slighty-darker vent.
Each ember resistant vent screen is custom-cut to fit your specific vents, and attaches over the existing opening with screws or staples.
With ember screen installation, you’re basically adding a new layer of defense on top of your existing vent, which is far less work and cost comapred to replacing the vent with a retrofit solution.
You can install ember resistant vent screens yourself, too, using our Ember Mesh Screen Installation Guide.
If you’re in San Diego County, our Total Screen team can professionally install ember screens for you; contact us today for your free, on-site, ember screen assessment.
Our ember screens are made from an approved and listed material in the California State Fire Marshal’s Wildland-Urban Interface (WUI) Product Handbook (a requirement for insurance discounts).
Benefits to Ember-Resistant Vent Screens:
- Meets or exceeds Chapter 7A standards for ember resistance.
- Less expensive than full vent replacements.
- Quick to install; often a DIY project.
- Maintains existing vent while adding ember defense.
- Screens are Recognized by insurers under California’s “Safer from Wildfires” program.
For details on how embers interact with vents, read Total Screen's article about Fire Protection for Home Vents, which explains how different vents each pose unique risks.
Ember Screens and Insurance Benefits
Many insurance companies in high-fire-risk areas offer premium discounts when homeowners install ember-resistant vents or screens.
Total Screen’s article on California Home Insurance in High Fire Risk Areas explains how insurers recognize ember-screen installations under California’s “Safer from Wildfires” framework.
Choosing the Right Solution for Your Home
When deciding between full vent retrofits and ember screens, consider the following:
- Age of your home. Homes built before 2008 rarely include ember-resistant vents—older building codes permitted ¼-inch mesh, which laboratory studies show can allow embers to ignite fine fuels [2]. If your vents predate Chapter 7A, installing screens or retrofits is essential. Newer homes may already meet Chapter 7A standards, but you should still inspect vent condition & mesh size.
- Risk level. Homes in very high fire-hazard severity zones, or those near dense vegetation might justify the added expense of intumescent/ retrofit vents for maximum protection.
- Budget and DIY appetite. Ember resistant vent creens are budget-friendly, and straightforward to install. Ember resistant vent retrofits are costlier, but can be viewed as a long-term investment.
- Insurance incentives. Check whether your insurer offers discounts for ember-defense measures. Both ember screens and retrofit ember vents typically qualify, when installed correctly.
Regardless of which ember-defense option you choose, covering every vent opening on your home is critical.
Un-covered vents provide direct pathways for embers to enter attics and crawl spaces, and millions of embers generated during a wildfire can land on a single property and enter through vents or windows [4].
Hardening these entry points, alongside creating defensible space around your home, dramatically improves your chances of survival.
Building a Culture of Ember-Defense
Upgrading vents is not only about protecting your own property; it contributes to community resilience.
NIST warns that embers not only ignite structures but also generate additional embers, creating a domino effect where one burning home threatens its neighbors [3].
By installing ember-resistant vents or screens, you reduce the chances that your house becomes a source of embers and help safeguard your neighborhood.
For a deeper understanding of wildfire trends and home-hardening strategies, explore Total Screen’s article on Wildfire Info – A Century of U.S. Data.
Take the Next Step with Total Screen
Ember-resistant vents and screens are a small upgrade that provide outsized protection.
Whether you choose to retrofit your vents or install custom Ember Screens, taking action now can significantly reduce your home’s vulnerability to wildfire embers.
Visit Total Screen or call 1-619-871-7610 to discuss your specific needs and schedule an installation.
When you harden your home and encourage your neighbors to do the same, you help build a fire-resilient community and set an example of proactive wildfire preparedness.
Sources
[1] Fire Safe Marin – “Fire-Resistant Vents.” Outlines homeowner guidance to replace ¼-inch screens with ⅛-inch or 1⁄16-inch wire mesh, avoid fiberglass or plastic mesh, and protect eave vents with baffles backed by 1⁄16-inch mesh. The page also quotes Chapter 7A, stating that vents must “resist the intrusion of embers and flames” and be protected by corrosion-resistant, noncombustible mesh with 1⁄16- to 1⁄8-inch openings. (https://firesafemarin.org/harden-your-home/fire-resistant-vents/)
[2] Lake County Fire Safe Council – “Vents.” Explains that the building code allows 1⁄8-inch mesh but notes that 1⁄8-inch is still better than ¼-inch, and embers passing through 1⁄8-inch screening can ignite fine fuels. Summarises Chapter 7A requirements: vents must resist ember and flame intrusion or be covered by corrosion-resistant, noncombustible mesh; 1⁄8-inch mesh is permitted and preferred; and vents in eaves must prove ember resistance. (https://firesafelake.org/vents/)
[3] National Institute of Standards and Technology (NIST) – “Exposures During WUI Fires.” Highlights that embers can travel miles ahead of a wildfire and ignite spot fires ahead of the main flame front, can ignite structures and parcel-level features, vary in size, and may cause ignitions hours after the flame front has passed. (https://www.nist.gov/el/fire-research-division-73300/wildland-urban-interface-fire-73305/hazard-mitigation-methodology-4)
[4] U.S. Fire Administration – “Protecting Structures From Wildfire Embers and Fire Exposures.” Notes that embers can be carried by winds and deposited several miles downwind, that millions of embers may impact a single structure, that embers can enter a building through windows or vents, and that embers can smolder for hours before igniting. (https://www.usfa.fema.gov/blog/protecting-structures-from-wildfire-embers-and-fire-exposures/)
[5] UC ANR Fire Network – “Vents.” Describes ember-resistant vent examples: Vulcan vents with a honeycomb matrix coated in intumescent paint, Brandguard vents using a baffle design, and Embers Out vents with multiple layers of louvers. Also summarises Chapter 7A provisions requiring corrosion-resistant, non-combustible mesh with 1⁄16- to 1⁄8-inch openings and prohibiting vents in eaves unless they resist embers and flames. (https://ucanr.edu/program/uc-anr-fire-network/vents)
[6] Chubb – “Help protect your home from wildfires with ember-resistant vents.” Explains that ember-resistant vents may use a combination of wire mesh, baffles, louvers and other design elements; that mesh alone is not always sufficient for eave and cornice vents; and that appropriate materials include stainless steel, galvanized steel, copper and intumescent coatings, while fiberglass and plastic should not be used. (https://www.chubb.com/us-en/individuals-families/resources/protect-your-home-from-wildfires-with-ember-resistant-vents.html)