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Dryer vents versus mesh
Do not cover a dryer outlet with 1/16–1/8 inch mesh. IBHS Wildfire Prepared Essential requires a working louver or flap on forced-air vents such as dryers, in lieu of mesh, so lint does not pile on a screen. Enhanced also wants metal duct and a metal hood. Mesh stays the prescriptive path for attic, gable, and crawlspace vents. A listed ASTM E2886 eave vent is not a dryer vent.
You are at the dryer hood on the wall. Lint plus a screen is fuel. IBHS wants a working flap, not mesh on that outlet.
See ember-resistant vents and mesh versus listed vents for the building-ventilation choice.
Why it matters
A dryer pushes lint. Mesh is a strainer. The lint sits on the screen, blocks airflow, and is fuel for embers at the wall. IBHS therefore carves dryers, and other forced-air outlets such as central vacuums, out of the mesh rule and asks for a flap that closes when the appliance is off. Enhanced also wants a noncombustible (metal) duct and hood.
That is the opposite of an attic vent, where you want a permanent 1/16–1/8 inch metal opening or a tested assembly. One hardware-store trip that meshes every hole will fail the dryer line on purpose.
How it works
Building ventilation (attic, gable, soffit, crawlspace) is a hole that stays open. Mesh answers ember size. ASTM E2886 answers whether a vent assembly resists embers and flame in a lab. That test method is the performance path for those openings.
A dryer is a forced-air exhaust. When it runs, the flap must open so lint and moisture leave. When it stops, the flap must close so embers do not ride in. Mesh on that outlet collects lint. Lint is fuel. Plastic accordion duct in the wall is not the Enhanced metal path, even if the hood looks like metal from the street.
IBHS’s December 2025 technical standard states the same split. Prescriptive mesh, openings not more than 1/8 inch, or a listed flame- and ember-resistant vent, for building ventilation. Forced-air vents (dryer and central vacuum) get a functional louver or flap in lieu of mesh. Plumbing vents are excluded from that mesh-or-listed rule. Enhanced adds that the forced-air vent itself must be noncombustible, for example metal.
CAL FIRE’s home-hardening page is about attic and underfloor vents. Cover those with 1/16–1/8 inch metal mesh or an OSFM listed flame- and ember-resistant vent. It does not turn the dryer into that product.
California Safer from Wildfires credits 1/16–1/8 inch metal mesh on exterior vents. That is a California insurance-credit recipe for building ventilation. It is not a dryer-hood listing and not Oregon law. See Safer from Wildfires is not Oregon law.
The two jobs
| Opening | Usual wildfire path | Do not |
|---|---|---|
| Attic, gable, soffit, crawlspace | Corrosion-resistant metal mesh 1/16–1/8 inch, or an ASTM E2886 listed vent | Leave 1/4 inch animal screen. Use plastic mesh. Cover the dryer with that same screen. |
| Dryer and similar forced-air outlets | Working louver or flap. Metal duct and hood at IBHS Enhanced. | Cover the outlet with ember mesh. Spec a listed eave vent as if it were a dryer hood. |
| Plumbing vent | IBHS excludes it from the mesh-or-listed-vent rule | Treat it as a dryer. Treat it as an eave vent under the 12-foot rule. |
Oregon R327, where adopted, says the mesh or ember-and-flame vent rule for enclosed attics, soffits, rafter spaces, and underfloor spaces (R327.3.2). It also keeps minimum net area under R408 and R806. It does not name the dryer. Do not mesh the dryer because the adopted code said “all ventilation openings.” Ask the authority having jurisdiction (the building official) if you are unsure how they treat the dryer hood on an R327 job.
A bath or kitchen fan that dumps at the wall or eave is not named on the IBHS dryer line. Do not guess. Confirm with the official. Note every hole in the soffit, including dryer and bath fans that dump at the overhang. See eaves.
An unvented attic removes attic ventilation openings. It does not finish the dryer.
What you actually buy. A working flap, and metal at Enhanced. This site has no dryer-vent SKU. The 8165 records under vents are building ventilation. Example listed eave and soffit models such as Vulcan eave round (8165-2192:0500) and BrandGuard soffit and undereave (8165-2232:0500) do not become legal dryer outlets because they are listed. Confirm the live listing if you spec them for the attic or soffit job they actually name. How to read a listing.
IBHS is a designation, not adopted code. Do both when both apply. IBHS does not replace adopted code.
What people mix up
- One trip to the hardware store, mesh on every hole in the house, including the dryer.
- A plastic flap that is broken open, or a hood with no flap.
- Plastic accordion duct in the wall, then a metal-looking hood on the siding.
- Buying a listed gable or soffit vent from the OSFM handbook and cutting it in as a dryer termination.
- Treating the dryer as an eave-vent problem under the 12-foot rule.
- Meshing a plumbing vent because IBHS said to cover vents. Plumbing vents are excluded.
- Treating a listed 8165 model as a dryer hood because the listing says ember-resistant.
- Closing the attic (unvented) and assuming the dryer outlet is done.
How to check
- Stand outside at the dryer hood. If you see mesh, that fails the IBHS dryer line.
- Run the dryer. The flap should open. When it stops, the flap should close. A stuck-open louver is not a working flap.
- If the owner wants IBHS Enhanced, the duct and outlet should be metal, not plastic.
- Walk the other vents separately. Attic, gable, ridge, soffit, foundation. Those still need mesh or a listed vent. See how to read a listing if the official wants a model number.
- Look at plumbing vents and bath fans as their own openings. Do not apply the dryer rule or the attic-mesh rule by habit.
- Clean the lint path. A correct flap still fails if the pipe is packed.
Limits
This page does not size dryer duct, does not replace mechanical code, and does not sell a hood. It does not decide what your building official will stamp on an R327 drawing. IBHS is a designation, not adopted code. Do both when both apply. It does not make the house fireproof. FireApproved is not the building official and not a listing body.
Related records
Questions
Can I cover the dryer vent with 1/8 inch mesh?
Not if you are following IBHS Wildfire Prepared. Essential requires a working louver or flap on forced-air outlets such as dryers and central vacuums, in lieu of mesh. Mesh on a dryer collects lint. Lint is fuel.
Do I need an ASTM E2886 listed dryer vent?
The listed vents on this site are attic, gable, soffit, and similar building ventilation. They are not dryer outlets. IBHS is asking for a flap that closes when the dryer is off, and metal duct at the Enhanced level, not an eave-vent listing.
Does Oregon R327 require mesh on the dryer?
R327.3.2 is about attic, soffit, rafter, and underfloor ventilation openings. It does not name dryer outlets. Do not mesh the dryer because a wildfire checklist said to cover the vents. Confirm with the building official if R327 is adopted on the lot.
Is the plastic foil duct a wildfire product?
IBHS Enhanced wants the dryer vent made of noncombustible material, for example metal, with a working flap. Plastic accordion duct is not that path.
What about plumbing vents and bath fans?
IBHS excludes plumbing vents from the mesh-or-listed-vent rule. It names dryers and central vacuums as the forced-air exception that needs a flap instead of mesh. A bath or kitchen exhaust that dumps at the wall or soffit is not named. Ask the building official. Do not mesh a dryer because the attic rule said “all vents.”