Raccoons and squirrels in Ottawa attics: signs, seasons and the humane one-way-door method
Updated
How to tell what is in your attic, why the time of year changes the plan, what Ontario's 1 km and 24-hour release rule means, and how a one-way door exclusion is done properly.
Signs something is living up there
The noise usually gives it away first. Squirrels are active by day, so scratching and running tend to start early in the morning and pick up again in the late afternoon. Raccoons are mostly active at night. They sound heavier, with thumps and dragging around dusk and before dawn.
From outside, walk the roof line with binoculars. Look for chewed soffit or fascia, a torn roof vent, lifted shingles at a corner, a bent vent flap or a gap where the soffit meets the wall. Squirrels leave clean, round chew holes. Raccoons tear and pull.
Inside, look for flattened or stained insulation, droppings, a smell of urine, or water stains on the ceiling below.
One thing not to do: do not block a hole until you know nothing is inside. An animal sealed into an attic will either die there or chew a new way out, often through the soffit or roof deck.
Baby season changes the plan
The time of year matters more than anything else. The Toronto Wildlife Centre advises that a raccoon living in an attic from January to September should always be assumed to be a mother with babies. In that period, a one-way door can shut the mother out and leave the young trapped inside.
Raccoon mothers commonly move their young between dens, and the young are independent by the end of summer. Squirrels also raise young in attics. Either way, a good inspection checks for a nest before anything is sealed.
What Ontario law says
Ontario lets a property owner, or an agent acting for them, deal with wildlife that is damaging their property. A wildlife removal business can act as your agent to capture and release animals, though not to kill them.
Ontario's list of who can act as your agent is short. It includes a licensed trapper, a person with a valid Outdoors Card and hunter accreditation (to harass or kill, not capture), a municipal employee doing wildlife control, an immediate family member, a wildlife removal business (capture and release only), and anyone the ministry authorizes.
The release rules are strict. Captured live wildlife must be released within 1 km of where it was caught and within 24 hours. It can only be released on private land with the landowner's permission. Species listed as endangered or threatened need a separate permit.
In practice this means trapping a raccoon and driving it out of the city is not allowed. And trapping alone solves little. The animal ends up close by, and the hole in your roof is still open for it or the next one.
How the one-way-door method works
The humane approach removes the animal by letting it leave on its own, then sealing the way back in.
First, the whole roof line is inspected, including the areas away from the obvious hole. Soffits, vents, chimney, plumbing stacks and roof-to-wall joints all get checked.
Second, every secondary gap is sealed, so the main entry is the only way out.
Third, a one-way door is mounted over the main entry. The animal leaves to feed and cannot get back in.
Fourth, the door stays up for several days while activity is checked. Only when the attic is quiet does the door come off and the opening get sealed with heavy-gauge steel screening fixed to solid framing.
If young are present, the job either waits until they are mobile, or the young are removed by hand and placed outside the entry so the mother can move them. Ask any operator you hire how they handle this before work starts.
After they are out
Once the animals are gone, the attic needs a look. Soiled insulation and droppings should be removed with proper protective equipment.
Before the job is signed off, the attic should be checked one more time for noise or fresh damage. Ask whether the exclusion work comes with a written guarantee on the sealed openings, and for how long.
Prevention is mostly about the roof. Chimney caps, screened vents and trimmed branches that no longer reach the roof all help.
Indicative 2026 ranges from the price guide on this site, before HST: an inspection is $100 to $250 and is often credited to the job. Raccoon removal with a one-way door and screening runs $400 to $1,000. Squirrel removal and exclusion runs $300 to $800. Attic clean-up and re-insulation is quoted after inspection, often $1,500 to $5,000.