Ridge vents versus ASTM E2886

A ridge vent is still an attic ventilation opening if it exists. ASTM E2886’s public scope evaluates gable-end, foundation, vertical-wall, and under-eave vents. It excludes roof ridge and off-ridge (field) vents (ASTM record). Metal is not that test. Where Oregon R327 is adopted, R327.3.2 still wants 1/16 to 1/8 inch mesh, or a vent designed to resist burning embers and flame, on the attic openings you kept (amendment PDF).

You are on the roof at the ridge cap. The baffle looks like metal. That is a material. It is not an 8165 eave listing and not an E2886 specimen.

The E2886 rig drawing (MECH-001) lives on the standard page. It is not a ridge detail. Do not use a house-level hub graphic as this joint.

Why it matters

Embers enter attics at every hole that remains. A listed eave vent does not cover the ridge because the brand matches. An unvented attic removes the hole. A metal ridge roll that was sold as “fire-safe” is still a hole unless mesh or an approved device is actually there.

California CWUIC 504.10.2 is explicit. Off-ridge and ridge vents on a sloped roof get 1/16 to 1/8 inch noncombustible corrosion-resistant mesh. That is a different sentence from 504.10.1’s listed or E2886 path.

How the holes split

See mesh versus listed vents for the two-path choice on openings E2886 can actually test.

The paths

1. Keep a ridge vent (Oregon). Treat it as an attic ventilation opening under R327.3.2. Show mesh size or the approved device on the drawings. Do not claim an E2886 pass for a geometry the standard excludes.

2. Keep a ridge vent (California mapped lot). Read CWUIC 504.10.2 for sloped-roof ridge and off-ridge mesh. Do not import Oregon’s underside-eave ban onto the ridge.

3. IBHS. The December 2025 technical standard includes ridge ends among ventilation openings that need the performance option (named E2886 criteria) or mesh not exceeding 1/8 inch. If E2886 excludes the geometry, the mesh path is the one that can exist on that ridge. Confirm with the designation reviewer.

4. Unvented. No ridge opening. Remaining dryer, gable, and crawl openings still need their own path.

5. Listed 8165 models on this site are eave, soffit, and gable specimens. Examples: Vulcan eave round (8165-2192:0500), BrandGuard soffit and undereave (8165-2232:0500). They are not ridge SKUs.

What people mix up

• Calling a metal ridge roll ember-resistant because it is metal.
• Specifying an 8165 eave vent as the ridge product.
• Treating E2886 as a ridge test.
• Leaving 1/4 inch animal screen at the ridge after upgrading the gables.
• Treating the ridge as R327.3.2.1 (that sentence is the underside of eaves, soffits, and cornices).

How to check

1. Look at the roof. Is there a ridge or off-ridge field vent.
2. Read the listing orientation. If the PDF says gable or undereave, it is not this hole.
3. If you use mesh, measure the opening. 1/16 to 1/8 inch in Oregon R327.3.2. Not 1/4 inch.
4. Put the path on the drawings. A “metal ridge vent” note is not a mesh size.

Limits

This page does not spec a ridge-vent SKU. It does not rate airflow. Net free area still has to meet R408 and R806 where those apply. FireApproved is not the AHJ. E2886 does not provide acceptance criteria. Adopting codes do.

Related records

• Vents, roofing
• ASTM E2886
• Mesh versus listed vents
• Unvented attic