How Often Should You Get Your Dryer Vent Cleaned?
How often should you get your dryer vent cleaned? A look at Ontario's Fire Code recommendation, Ottawa's bylaw, and what gas dryer owners need to know.
DVSIC
7/29/20262 min read
It's one of the most common questions homeowners ask — and the honest answer is more specific than most people expect.
The short answer: twice a year
Ontario's Fire Code recommends dryer vent cleaning on a semi-annual basis — twice a year, not once. In some municipalities, that recommendation has become more than a suggestion. The City of Ottawa passed a bylaw that turned the province's semi-annual guideline into a binding legal maintenance requirement, not a voluntary best practice.
That's a meaningful distinction. A lot of general advice online treats dryer vent cleaning as a once-a-year, "set it and forget it" task. In at least one Canadian jurisdiction, the actual fire code standard is stricter than that — and your local fire code may be too, depending on where you live.
If you have a gas dryer, there's an additional requirement
Gas-fired dryers carry an extra layer of risk beyond lint buildup: a restricted vent can allow combustion by-products, including carbon monoxide, to back up instead of exhausting properly.
Because of this, provincial technical safety authorities commonly recommend that gas-fired dryers be serviced at least annually by a licensed gas contractor — in addition to, not instead of, routine dryer vent cleaning. If you have a gas dryer, that's a second, separate maintenance item worth keeping on your calendar alongside vent cleaning itself.
Why the frequency matters more than people think
A dryer vent doesn't fail all at once. Lint accumulates gradually, restricting airflow a little more with every load. By the time you notice the warning signs — clothes taking longer to dry, the dryer feeling unusually hot, a burning smell during a cycle — the vent has often been restricted for a while already.
Twice-a-year cleaning catches that buildup before it becomes a real hazard, rather than waiting for a warning sign to show up first.
The bottom line
General recommendation: twice a year (semi-annual), per Ontario's Fire Code
Some municipalities: legally required on that schedule, not just recommended
Gas dryers: an additional annual service by a licensed gas contractor, on top of routine vent cleaning
Local bylaws vary — it's worth checking whether your municipality has made this a legal requirement rather than a guideline
If it's been more than six months since your dryer vent was last cleaned, it's a reasonable time to book a service — regardless of whether you've noticed any warning signs yet.
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