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Cluster fly control for a Kitchener attic and windows — KW Pest Control

Kitchener · Waterloo · Cambridge · Guelph

Fly ControlIn Kitchener-Waterloo

KW Pest Control treats cluster flies and house flies in homes and businesses in Kitchener, Waterloo, Cambridge and Guelph. For cluster flies, we treat the attic and the outside walls where flies gather, ideally in spring and again in fall. Fly treatment, including attic treatment, typically costs about $400 to $500 before HST. Call 519-957-1766.

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Cluster flies: the slow flies at your windows

If you find slow, sluggish flies buzzing at sunny windows in fall, late winter or on warm winter days, they’re almost certainly cluster flies. They’re a little larger than a house fly, dark grey, with golden hairs on the thorax, and they overlap their wings when resting.

Cluster flies don’t breed in garbage or food. Their larvae live in soil and feed on earthworms, which is why homes near lawns, fields and green space in Kitchener-Waterloo, Cambridge and Guelph get so many. In late summer and early fall, adults gather on sunny south- and west-facing walls, then crawl into attics, wall voids and window frames to spend the winter. On warm days they wake up and wander into the living space, toward the light.

Close-up of a house fly on a leaf

House flies, fruit flies and drain flies

For these flies, the fix starts with finding and removing the breeding source. Treatment helps knock down adults, but sanitation is what solves it. For restaurants and food businesses, see commercial pest control.

  • House flies breed in garbage, compost, pet waste and food scraps. Indoors, they mean there’s a breeding source nearby, often a bin, compost or drain.
  • Fruit flies breed in overripe fruit, recycling, drains and spilled juice or alcohol, which makes them common in kitchens, bars and restaurants.
  • Drain flies are small and fuzzy and breed in the slime inside drains.

Our fly control process

  1. Phone estimate.Tell us what the flies look like, where you see them and when. The estimate is free.
  2. Identify the fly.Cluster flies, house flies and fruit flies need very different approaches.
  3. Cluster fly treatment.We treat the attic and exterior walls, eaves and window frames where cluster flies gather and get in. Spring and fall treatments work best, and homes with heavy problems benefit from both.
  4. Source control for other flies.We find breeding sources and tell you what to clean, seal or move.
  5. Prevention.We point out gaps around windows, soffits, vents and siding to seal.

When to treat for cluster flies

Timing matters. A fall treatment, from late August to early October, targets flies as they gather on walls and move into the attic. A spring treatment catches flies coming out of the walls and attic as the weather warms. Treating in mid-winter doesn’t help much, because the flies are deep in wall voids.

How much does fly control cost?

Fly treatment, including attic treatment, typically costs about $400 to $500 before HST. Larger homes and homes with more than one attic cost more. Spring and fall treatments are recommended for cluster flies. Your technician confirms the price before starting. See the pest control cost guide.

How to keep flies out

Fewer flies also means fewer spiders. See spider control.

  • Seal gaps around windows, soffits, siding, vents and utility lines in late summer.
  • Repair torn window and door screens.
  • Keep garbage and green bins sealed and clean, and empty them often.
  • Rinse recycling and clean up pet waste in the yard.
  • Store fruit in the fridge and clean drains regularly.
  • Vacuum dead cluster flies from windows and sills; dead flies can attract carpet beetles.

Fly control in Kitchener, Waterloo, Cambridge and Guelph

KW Pest Control serves homes and businesses in four cities: Kitchener, Waterloo, Cambridge and Guelph. That includes downtown Kitchener and Doon, Uptown Waterloo and Beechwood, Galt, Preston and Hespeler in Cambridge, and every Guelph neighbourhood from the Ward to the south end. Not sure we cover your street? Call 519-957-1766 and ask.

Kitchener · Waterloo · Cambridge · Guelph

Kitchener Waterloo Cambridge Guelph

Fly control: FAQ

Why do I have flies in my house in winter?
They’re almost always cluster flies. They crawl into attics and wall voids in fall to overwinter, then wake up on warm, sunny days and wander toward the light in your rooms. They don’t breed indoors, so the flies you see came in last fall. A fall treatment and sealing gaps help prevent the next round.

How much does cluster fly treatment cost?
Fly treatment, including attic treatment, typically costs about $400 to $500 before HST. Larger homes and homes with more than one attic cost more. Spring and fall treatments are recommended for cluster flies, and your technician confirms the price before any work starts.

Are cluster flies harmful?
Cluster flies don’t bite, spread disease or breed in food, so they’re mostly a nuisance. They can be a big one, with hundreds collecting at windows, and dead flies in walls and attics can attract carpet beetles and other insects. Treating in spring and fall and sealing entry gaps keeps numbers down.

Do fly strips or zappers work?
They catch some flies, but they don’t solve the problem. Cluster flies keep coming out of the walls and attic, and house flies keep breeding at the source. Strips and zappers can help in a garage or barn, but treating where cluster flies overwinter, or removing the breeding source, is what makes a difference.

Get rid of flies. Call KW Pest Control.

Call 519-957-1766 and tell us what you’re seeing. Estimates over the phone are free, and an inspection is required for an exact quote on larger jobs. The office is open Monday to Friday, 8:30 a.m. to 5 p.m.; leave a message after hours and we’ll call you back the next business day. Call 519-957-1766 Send Us a Message

Request free estimate Call 519-957-1766
KW Pest Control

Local pest control for homes and businesses in Kitchener, Waterloo, Cambridge and Guelph. Licensed & insured. Free phone estimates.

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519-957-1766
Mon–Fri 8:30 a.m.–5 p.m.
Licensed & insured
Kitchener · Waterloo · Cambridge · Guelph

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