The short answer
Ember-resistant vents can be required for certain construction in wildfire-prone areas, but that does not mean every older San Diego home must immediately replace all of its existing vents. The answer depends on the property location, the work being performed and the code enforced by the local authority having jurisdiction.
California wildfire construction standards include specific requirements intended to reduce the entry of burning embers and flame through ventilation openings. San Diego County also maintains a Wildland-Urban Interface code for covered areas in the unincorporated County fire districts.
What California wildfire standards say about vents
California's wildfire-resistance provisions address ventilation openings at locations such as attics, gable ends, ridge vents, eaves, soffits, crawl spaces and foundations. For covered construction, the code calls for wildfire flame- and ember-resistant vents that are approved/listed for the purpose, or qualifying WUI vents tested to the applicable ASTM standard.
For some sloped-roof vent conditions, the code also specifies noncombustible, corrosion-resistant mesh within a defined opening-size range. A simple screen retrofit should not automatically be assumed to satisfy every permitted-project requirement.
Does an older San Diego home have to retrofit?
For an existing home with no current construction project, there is not one universal rule requiring every homeowner in San Diego County to replace every vent simply because the home is located in the county. However, requirements may be triggered by new construction, additions, alterations, repairs, rebuilding or other work subject to wildfire-resistance provisions.
Because San Diego County contains incorporated cities as well as unincorporated fire-district areas, the enforcing agency can differ by address. A homeowner in Poway or Escondido may be dealing with city requirements, while a property in an unincorporated community such as Ramona may fall under County rules. Always verify permit and code requirements with the building or fire authority responsible for the specific property.
Why homeowners still upgrade vents voluntarily
Even where a retrofit is not currently mandated, exterior vents are a common pathway for wind-driven embers. San Diego County wildfire-preparedness guidance specifically identifies roofs, attics, raised foundations and other vented spaces as areas where ember-resistant upgrades can reduce vulnerability.
That is why many homeowners consider vent upgrades as part of a broader wildfire home-hardening plan, alongside eave work, roof and gutter improvements, defensible space and other exterior measures.
What should you look for in an ember-resistant vent?
For code-related work, the product and installation should be appropriate for the specific opening and applicable standard. California's Office of the State Fire Marshal maintains listings of building products reviewed for compliance with wildfire construction requirements.
- Confirm the vent is appropriate for the opening and ventilation needs
- Ask whether the proposed product is listed or tested for wildfire flame and ember resistance
- Make sure the installation does not improperly reduce required ventilation
- Verify whether permits or inspections are required for the project
What if you are not sure which vents your home has?
A home-hardening assessment can identify attic vents, soffit vents, gable vents, crawlspace or foundation openings and other exterior vulnerabilities. From there, you can decide whether a repair, retrofit or full vent replacement makes sense.
See our main guide to ember-resistant vent installation in San Diego, or request a connection with a participating provider below.
What do ember-resistant vents cost?
For budgeting factors and quote comparisons, see our San Diego ember-resistant vent cost guide.
Official resources
For code or permitting questions, rely on the authority responsible for your property. Useful starting points include the San Diego County 2026 fire and WUI code resources, the County's Wildfire Prepared Home information, and the California State Fire Marshal building-materials listings.
Note: This page is general informational content, not legal, building-code or permitting advice. Requirements can vary by property and jurisdiction.
More vent guidance
See our guide to choosing ember-resistant vents and our explanation of how ember-resistant vents reduce a common wildfire vulnerability.