Vulcan Ember-Resistant Vents

How it works

A replacement vent that looks like a normal soffit, gable or foundation vent until it gets hot. Inside is an intumescent material that expands when exposed to fire or high heat and plugs the opening completely, sealing the attic or crawlspace against embers and flame. The rest of the year it ventilates normally, which is the whole trick — you cannot simply block a vent, because the building needs the airflow.

What the market looks like

Ember-resistant vents are a small but maturing market driven almost entirely by California building code. Chapter 7A of the California Building Code and the associated WUI listings created the demand, and the credible manufacturers — Vulcan, Brandguard, and a handful of others — all build to that standard. Prices run CAD $60–$220 per vent. Outside California there is no code requirement anywhere in North America yet, which means the market is entirely voluntary and most homeowners have never heard of the product. That is unfortunate, because attic vents are the single most common route by which embers get inside a house.

Features that actually matter

Intumescent closure

Expands and seals under heat. Passive, no power, no maintenance, nothing to activate.

Normal ventilation when cold

Net free area comparable to the vent it replaces, so you do not create a moisture problem in the attic.

WUI listing

Tested to California's Chapter 7A ember-intrusion and flame-impingement protocols. This is the only meaningful third-party validation in the category — ask for the listing number.

Standard sizes

Made in common North American vent dimensions so most swaps are drop-in.

Multiple types

Soffit, gable, dormer, foundation and roof vents — you generally need a mix.

What it really costs

Up front

CAD $70–$220 per vent. A typical bungalow has 8–20 vents; a two-storey with a complex roof, 20–40.

Consumables

None. Passive device, no service parts.

What else you'll need

Cross-border shipping if buying US product into Canada, plus duty. Paint if you want them to match.

Over five years

Nil. This is genuinely buy-once.

Figures are typical street prices in Canadian and US dollars as of September 2026, gathered from public retail listings. They move with the season and with the exchange rate — treat them as a planning band, not a quote.

How it differs from the alternatives

Versus 1/8 in ember mesh

Mesh is a tenth the price and stops the majority of embers. It does not stop flame impingement and it does not seal. If budget is tight, mesh everything first — then upgrade the two or three vents most exposed to the fuel.

Versus Brandguard

Broadly equivalent performance and price. Brandguard uses a baffle-and-mesh geometry, Vulcan an intumescent plug. Vulcan tends to be easier to source in Canada; availability should probably decide it for you.

Versus blocking vents with plywood on the day

People plan this and then are not home, or are home and forget the crawlspace. A passive device does not depend on you.

The under-appreciated point

Vents are where houses actually get lost. Post-fire investigations keep finding intact exteriors with burned-out attics. This is not a glamorous purchase and it may be the highest-leverage one on the site.

If not this, then what

• Brandguard Ember & Flame VentsEquivalent alternative; buy whichever you can actually get.
• 1/8 in stainless ember meshA tenth the cost, most of the benefit for embers, none of it for flame. A legitimate stepping stone.