Moths in Your Closet? How to Get Rid of Clothes Moths for Good (Ontario)

Quick answer: Small holes in wool, cashmere or stored blankets are almost always clothes moths — not the fluttery moths that circle your porch light. The damage is done by the larvae, not the adults you see. Cedar and mothballs will not clear an established infestation. What works is a three-part reset: heat-wash or freeze every affected item, vacuum the closet aggressively (floor, baseboards, shelf corners, the underside of shelving), then seal what you cannot wash. If holes keep appearing after a full reset, the source is somewhere you have not found — usually a rug pad, an heirloom item, a stored duvet or a wool-blend carpet edge — and that is when a professional inspection earns its keep. Call Sani IQ at (705) 302-1887.

September is when Ontario homeowners find clothes moth damage, and the reason is simple: this is the month the wardrobe turns over. The wool sweaters come out of the bin, the good coat comes off the top shelf, the cottage blankets get folded and stored. And somewhere in that swap, someone holds a favourite sweater up to the light and finds three ragged holes across the shoulder.

Those holes were made months ago. The insect that made them is probably still in the closet.

Is it a clothes moth — or something else?

Most people’s first instinct is wrong here, and it costs them a season of treating the wrong thing.

The moths that flap around your kitchen light at night are almost never clothes moths. Clothes moths are small — roughly 6 to 8 mm — a dull buff or golden colour, and they actively avoid light. They do not flutter; they scuttle into a dark corner rather than fly across a lit room. If a moth flies confidently toward a lamp, it is not the one eating your sweaters.

The second common mix-up is pantry moths — a kitchen problem, a different species, living in dry goods like flour, cereal and pet food. If your moths are in the cupboard rather than the closet, that is a stored-product pest and the treatment is completely different.

The third mix-up, and the one that fools the most people, is carpet beetles. Their larvae also eat wool and the damage looks similar at a glance. The tell is what gets left behind: carpet beetle larvae shed bristly, tan cast skins that look like tiny hollow caterpillars, while clothes moth larvae leave silk — fine webbing, sometimes a small tube or case, and gritty frass the colour of the fabric they have been eating. Silk webbing on wool means moths.

Webbing vs. casemaking: the two species Ontario homes actually get

Two species matter here. Webbing clothes moths are the more common in Ontario homes; their larvae spin loose silk over the feeding area and stay under it, leaving patchy grazed areas — thinning in the pile of a wool rug, or a fuzzy silk film inside a folded sweater. Casemaking clothes moths build a portable silk case, drag it around and feed from inside it. The case takes on the colour of whatever they are eating, so on a navy sweater you are looking for a navy grain of rice. People routinely vacuum these up thinking they are lint.

Both feed exclusively on keratin, the protein in animal fibres. That is why they attack wool, cashmere, alpaca, silk, felt, feathers and fur while completely ignoring cotton and polyester — and why damage is so unevenly distributed: a moth will destroy one section of a wool-blend rug and leave the synthetic section untouched.

They also strongly prefer soiled fabric. Perspiration, body oils and food spills make a garment far more attractive, which produces the single most useful fact here: the sweater you wore twice and put away without washing is the one they went for.

Why cedar and mothballs disappoint

Almost every Ontario homeowner tries cedar first, and almost every one is disappointed.

Cedar oil can kill very young larvae in a tightly sealed container at high concentration. A cedar chest built in 1940 and open to the room ever since is not that — the volatile oils that do the work dissipate within a few years, and sanding to “refresh” the wood buys a short window at best. Cedar blocks and hangers in an open closet do essentially nothing to an established population.

Mothballs are a different problem. The active ingredients are real pesticides and can work, but only in a genuinely sealed container where the vapour builds up. Scattered in a closet they mostly just make your clothing smell while larvae feed a metre away — and they are not something to use casually around living space, children or pets. Read and follow the label; in Canada that label is the law.

Lavender sachets, essential oils and ultrasonic devices have no meaningful effect on an established infestation. They are pleasant. They are not treatment.

The reset that actually works

If you have found damage, do the whole protocol. Half of it does not work, because the larvae you miss simply repopulate the closet.

1. Empty the closet completely — including the things at the back you have not worn in three years, statistically the most likely source.

2. Sort into wash, freeze and clean. Anything washable gets a hot wash (60 °C where the care label allows) or a hot tumble dry — heat kills every life stage. Anything that cannot take heat goes into the freezer: bag it tightly, squeeze the air out, freeze at −18 °C for at least 72 hours. Dry cleaning also kills all stages, which is the right answer for tailoring and heirlooms.

3. Vacuum like you mean it. The step people skip, and the one that matters most. Eggs and larvae collect in closet floor corners, along baseboards, where carpet meets the wall, under and on top of shelving, and in the seams of storage bins. Use the crevice tool, and empty the vacuum outside immediately.

4. Wipe down the empty closet and let it dry before anything goes back in.

5. Store clean, store sealed. Soiling is the attractant, so everything goes back clean. Wool going away for the season belongs in a sealed bin or garment bag, not an open shelf.

6. Put out pheromone monitoring traps. They solve nothing on their own, but six weeks from now they tell you whether the population is actually gone.

This is not folk advice. The Canadian Conservation Institute, whose job is keeping museum textiles intact, builds its pest guidance around freezing and rigorous cleaning, and extension entomologists at the University of Kentucky and Michigan State put sanitation and heat or cold treatment ahead of anything you can spray.

The cottage-blanket problem

Cottage country has a particular version of this, and we see it every fall across Muskoka and Orillia. A wool blanket spends the winter folded in a closed cottage — no vacuuming, no disturbance, no laundering — and the warm months still give larvae enough time to complete development. When that blanket comes back to the city in September and goes into a closet, it arrives with a live population.

The same pattern shows up in city homes: the basement bin, the under-stair closet, the spare-room wardrobe nobody opens. Undisturbed plus wool plus soiled equals clothes moths, in Richmond Hill the same as in Gravenhurst. If you are closing a cottage this fall, launder or freeze the wool before it gets stored, not after.

When holes keep appearing

Run the full protocol once and most households are finished. If new holes show up two months later, something is still generating moths, and it is almost always one of these:

• A wool or wool-blend area rug, especially the section under furniture that never gets vacuumed
• The rug pad or underlay, often wool felt and almost never inspected
• A taxidermy piece, felt instrument case, sheepskin or feather pillow
• Carpet edges along baseboards, where the pile is dense and undisturbed
• An heirloom item — a christening gown, a uniform, a folded quilt — boxed in the basement

Finding the reservoir is the entire job at that point, and it is the part homeowners consistently cannot do alone — the source is by definition somewhere they have not thought to look. A professional inspection covers storage areas, rug underlays, upholstery seams, and the dead spaces where fibre and dust collect. Sani IQ starts every service with a $95 professional inspection, credited in full when you book the treatment. For a fabric-pest problem that has already survived one DIY round, that is the fastest route to an actual answer.

What treatment and protection cost

For a confirmed infestation, treatment is a targeted residential service — closet and storage areas, carpet edges, cracks and voids where larvae pupate — combined with the sanitation work above, which the homeowner still has to do. General Insect Control starts at $395 exterior, or $475 interior and exterior, with a 60-day guarantee.

But the honest recommendation is different, because a one-time treatment addresses the population you have today and nothing about next August.

Fabric pests are a slow, quiet, recurring problem. Larvae feed for months out of sight, so by the time damage is visible the population has been established for a season or more — and the conditions that let it establish are all still there after treatment. Our Insect Control plan is $845 a year, and it fits the shape of this problem: scheduled visits through the year, so a new population gets caught while it is still four larvae in a corner rather than after it has grazed a path across a cashmere coat.

In plain numbers, one good wool coat, one cashmere sweater and one wool area rug is well past $2,000 to replace. A year of protection is $845. The one-time treatment is the right entry point when you have a problem right now; the plan is what keeps you from having it again. Every option is on our plans and pricing page, or call (705) 302-1887.

Sani IQ is licensed under the Ontario Pesticides Act and registered with the MECP, BBB Accredited, carries $5M liability coverage, and holds a 5.0 Google rating. Our technicians are employed, licensed and background-checked — never subcontracted.

Frequently asked questions

Do clothes moths bite or carry disease? No. Adults do not feed at all. The damage is entirely from larvae eating fibre — this is a property-damage pest, not a health pest.

How long does it take to get rid of clothes moths? A full reset done properly usually resolves it, but you will not know for six to eight weeks — roughly one generation. Use pheromone traps to confirm, and do not declare victory on week two.

Will one hot wash fix it? It fixes that garment. It does nothing about eggs in the closet floor corners or larvae in the rug, which is why the vacuuming step is not optional.

Can clothes moths eat synthetic fabric? Not as a food source — they need keratin. But they will chew through a synthetic layer to reach wool underneath, and a 20% wool blend is still on the menu.