How to Get Rid of Ants in Your House: Ontario Homeowner's Guide

Common Ant Species in Ontario Homes

Ontario is home to several ant species that routinely invade residential properties. Each species has different nesting habits, dietary preferences, and responses to treatment — identifying which species you are dealing with is the essential first step before choosing a control method.

Carpenter Ants

Carpenter ants are the largest and most destructive ant species in Ontario homes. Workers range from 6 to 13 millimetres long — noticeably bigger than any other household ant. They are typically black, though some species are bicoloured (red and black). Their most distinctive feature is a smoothly rounded thorax when viewed from the side. Carpenter ants do not eat wood — they excavate galleries inside it to create nesting space, pushing out sawdust-like shavings (frass) as they work. They prefer wood softened by moisture, making them a reliable indicator of water damage in the building. Parent colonies are typically outdoors in dead trees, stumps, or woodpiles, while satellite colonies establish inside homes near moisture sources. For detailed carpenter ant information, see our carpenter ant identification guide.

Pavement Ants

Pavement ants are small (2.5 to 4mm), dark brown to black, with lighter legs and antennae. Originally from Europe, they thrive in Ontario's urban environments. They nest in cracks between sidewalk slabs, under driveways, and beneath foundation stones. During Ontario's cold winters, they actively move into heated buildings through foundation cracks and expansion joints. Pavement ants eat almost anything — sugar, grease, meat, crumbs, and dead insects. They are the most common ant seen forming trails across kitchen counters and floors in Ontario homes during late winter and early spring. They can sting but rarely do so unprovoked.

Pharaoh Ants

Pharaoh ants are tiny (only 2mm), yellowish to light brown, and nearly invisible to the casual observer. They are tropical insects that survive in Ontario exclusively inside heated buildings. They nest in wall voids, between studs, inside insulation, and near warm, humid areas close to food and water. Pharaoh ants are medically significant because they carry pathogenic bacteria including Salmonella, Staphylococcus, and Clostridium — making them a serious concern in hospitals and food preparation areas. They are the hardest ant species to control because they respond to disturbance by splitting into multiple satellite colonies (called budding), which makes spray treatment counterproductive.

Odorous House Ants

Odorous house ants are small (2 to 3mm), dark brown to grey, and identified by the distinctive rotten coconut smell they release when crushed. They form large colonies and frequently establish satellite nests near the main colony. Indoors, they nest in wall voids, beneath floors, around hot water pipes, and in insulation. They are generalist feeders attracted to sugary foods, dairy, vegetables, and crumbs. Odorous house ants create visible trails along countertops, sinks, and cabinet edges as they recruit colony mates to discovered food sources. They are a nuisance pest — no structural damage, no bites — but their large colony sizes and multiple nesting sites make elimination challenging.

Citronella Ants

Citronella ants (yellow ants) are 3 to 4.5mm, light yellow to light brown, and produce a distinct lemon-like odour when crushed. They are primarily subterranean, nesting under concrete slabs, patios, walkways, and in soil around foundations. Homeowners most often encounter them when winged swarmers emerge indoors in mid to late summer, sometimes in large numbers that cause alarm. Citronella ants feed exclusively on honeydew produced by root aphids, which means conventional sugar or protein baits do not attract them. Their presence typically indicates high soil moisture near the foundation. They do not damage structures or contaminate food — their indoor appearance is usually limited to brief swarming events.

Why Species Identification Matters for Treatment

Treating ants without identifying the species first wastes time and money — and can make the problem worse.

Treatment Response Varies by Species

Sugar-based baits are highly effective against pavement ants and odorous house ants but useless against citronella ants that feed on honeydew. Protein-based baits work better for carpenter ants than sweet baits alone. Repellent sprays cause pharaoh ant colonies to split into multiple satellite nests, expanding the infestation. Perimeter barrier treatments prevent pavement ant entry but do not address carpenter ant satellite colonies already inside the walls. Choosing the wrong treatment approach for the species present delays resolution and may require starting the entire process over once the species is correctly identified.

How to Identify Your Ants

Start with size: if the ants are large (6mm or more), they are almost certainly carpenter ants. If they are very small (2mm) and yellow, suspect pharaoh ants. Medium-small dark ants (2 to 4mm) are likely pavement ants or odorous house ants — crush one and smell it. A rotten coconut odour confirms odorous house ants. If you find piles of sawdust-like material beneath wooden structures, carpenter ants are present. If you are uncertain, capture several ants in a sealed container and show them to a pest control professional for identification. Accurate identification before treatment saves significant time and expense.

Common Identification Mistakes

The most common misidentification is confusing carpenter ant swarmers with termite swarmers. Both are large winged insects that appear indoors in spring. The distinguishing features: ants have elbowed (bent) antennae, a narrow pinched waist, and front wings that are longer than back wings. Termites have straight, bead-like antennae, a thick waist with no visible pinch, and four wings of equal size. Correct identification is essential because carpenter ant treatment and termite treatment are entirely different programs. Another common mistake is assuming all small black ants are the same species. Pavement ants, odorous house ants, and pharaoh ants all appear as small dark ants to the untrained eye, but they require different treatment approaches. When in doubt, collect samples and get professional identification before investing in treatment products.

Signs of an Ant Infestation

Ant infestations often start small and grow rapidly. Recognising the signs early allows intervention before colonies establish deep inside the structure.

Visible Ant Trails

The most obvious sign is a line of ants moving along a consistent path — along a baseboard, across a counter, up a wall, or along a window frame. These trails follow pheromone paths laid by scout ants that found food or water. The trail will lead back to the nest entry point if you follow it in the direction opposite the food source. Trails are most active during warm months but pavement ants may trail indoors year-round in heated Ontario homes. The width and activity level of the trail indicates colony size — a thin line of a few ants suggests early-stage entry while a broad, busy stream indicates an established colony nearby. Multiple trails in different rooms suggest more than one entry point or a large colony with foragers exploiting several food sources simultaneously.

Frass Piles (Carpenter Ants)

Carpenter ants push excavated wood shavings out of their galleries through small openings called kick-out holes. The resulting frass piles look like fine sawdust mixed with insect body fragments, often found on floors, windowsills, or countertops beneath wall voids, wooden beams, or door frames. Frass is distinct from sawdust left by woodworking because it contains fragments of insect parts mixed with the wood fibres. Finding frass confirms active carpenter ant gallery excavation and warrants immediate investigation. For a visual identification guide, see our carpenter ant identification page.

Winged Swarmers

Finding large winged ants emerging from walls, window frames, or floor gaps inside your home — particularly in spring — indicates a mature colony that has been present long enough to produce reproductive individuals. Carpenter ant swarmers are large (up to 25mm with wings) and typically emerge between May and July. Indoor swarmers confirm a colony inside the building structure, not just ants entering from outside. A single swarming event can produce dozens to hundreds of winged ants. Collect several for identification — carpenter ant swarmers are sometimes confused with termite swarmers, and the distinction is critical because treatment approaches differ entirely.

Sounds in Walls

A large carpenter ant colony produces faint rustling or crinkling sounds inside wall voids, audible when the house is quiet at night. The sound is caused by hundreds or thousands of ants moving through their gallery system. It is more subtle than mouse scratching — a light, papery rustling rather than the distinct scraping of rodent claws. If you suspect ants in a wall, press your ear against the wall and tap firmly — the disturbance often triggers increased ant movement that makes the rustling temporarily louder and easier to hear. The sound is most noticeable on warm evenings when ant activity peaks. If you can hear carpenter ants in a wall, the colony is likely substantial — containing thousands of workers — and professional treatment is warranted rather than DIY approaches that may not reach the gallery system deep inside the wall structure.

Carpenter Ants: The Structural Threat

Carpenter ants are the only ant species in Ontario that causes structural damage. Because the damage is hidden inside walls and is often connected to moisture problems, carpenter ant infestations require more aggressive investigation and treatment than other species.

The Moisture Connection

Carpenter ants do not infest sound, dry wood. They establish galleries in wood that has been softened by moisture — around leaking plumbing, in water-damaged walls, behind improperly flashed windows, in roof areas affected by ice dams, and in wood contacting damp soil. Finding carpenter ants almost always means there is also a moisture problem that must be corrected. Treating the ants without fixing the moisture source leads to reinfestation because the conditions that attracted them remain. When a pest control technician treats carpenter ants, the treatment should always include identifying and recommending repair of the underlying moisture issue.

Parent Colonies vs Satellite Colonies

Carpenter ant parent colonies are typically outdoors — in dead trees, stumps, fence posts, or woodpiles within 30 to 100 metres of the home. Satellite colonies establish inside the building, connected to the parent colony by foraging trails that workers travel regularly. A home may have multiple satellite colonies in different locations. Effective treatment must eliminate both the satellite colonies inside the building and address the parent colony outdoors, or foraging workers will re-establish satellite nests inside the home. This is why perimeter treatment and removal of outdoor harbourage (dead trees, stumps, wood piles near the house) are essential components of carpenter ant management.

Assessing Damage

Carpenter ant damage is typically localised near the moisture source and may not be visible without probing. Tap suspect wood with a screwdriver handle — damaged wood sounds hollow compared to solid wood. Probe with the screwdriver tip — galleries are smooth, clean tunnels running parallel to the wood grain, distinct from the rough, mud-packed tunnels of termites. Damage concentrated around plumbing fixtures, window frames, door frames, and exterior wall cavities where moisture intrusion occurs is characteristic of carpenter ants. Severe damage in load-bearing members requires assessment by a structural engineer. For a comparison with termite damage, see our termite damage signs guide.

Common Carpenter Ant Locations in Ontario Homes

Carpenter ant satellite colonies establish in predictable locations tied to moisture. The most common sites include bathroom walls near showers and tubs where grout and caulk failures allow water behind the wall finish, kitchen walls behind dishwashers where supply line connections slowly leak, window frames and sills with failed caulking or flashing that allows rain infiltration, porch and deck attachment points where moisture wicks from the structure into the building framing, roof areas below ice dam zones where repeated freeze-thaw cycles drive water under shingles and into soffits, and basement rim joists where condensation collects on the cold surface during humid months. In Ontario's climate, the freeze-thaw cycle creates new moisture intrusion pathways every year, making annual inspection of these high-risk locations an essential part of carpenter ant prevention.

DIY Ant Control Methods

DIY methods work well for early-stage infestations of sugar-feeding species (pavement ants, odorous house ants) and as a first line of defense before deciding whether professional treatment is necessary.

Baiting vs Spraying

Baiting is far more effective than spraying for ant control. Spray kills only the ants it contacts — a small fraction of the colony. The queen and thousands of remaining workers inside the nest are unaffected, and killed foragers are replaced within days. Baiting works differently: foraging ants carry poisoned food back to the nest where it is shared with the queen, larvae, and other workers, killing the colony from the inside. The bait must be slow-acting enough that foragers survive long enough to deliver it to the nest before dying. Fast-acting contact sprays disrupt this process and should be avoided.

Borax Sugar Bait

Borax (sodium borate) mixed with sugar is an effective, inexpensive homemade bait for sugar-feeding ants. Mix one part borax with three parts white sugar and add enough warm water to form a syrupy liquid. Place small amounts in shallow containers (bottle caps work well) along identified ant trails. The sugar attracts foragers and the borax kills them over 24 to 48 hours — slow enough for workers to carry the bait back to the nest and share it. Refresh the bait every two to three days. This method is effective for pavement ants and odorous house ants but not for carpenter ants (which prefer protein-based food) or pharaoh ants (which require commercial slow-acting gel baits).

Commercial Gel Baits

Commercial ant gel baits available at hardware stores contain slow-acting insecticides (typically fipronil, indoxacarb, or imidacloprid) in an attractant matrix. Apply small drops along ant trails, near entry points, and inside cabinets where ants have been seen. Do not apply spray insecticide near gel baits — the repellent effect of the spray prevents ants from reaching the bait. Gel baits are available in sugar-based and protein-based formulations. If ants ignore the sugar bait, switch to protein — some species and some colonies prefer one over the other depending on the colony's current nutritional needs. Allow two to three weeks for full colony effect before evaluating success.

Diatomaceous Earth

Food-grade diatomaceous earth (DE) is a physical rather than chemical treatment. The fine powder contains microscopic fossilised diatom shells with sharp edges that damage the waxy outer coating of insect exoskeletons, causing dehydration. Apply a thin layer of DE in cracks, along baseboards, around pipe penetrations, and inside wall voids accessible through electrical outlet openings (turn off power first). DE works slowly and is most effective as a supplementary measure rather than a standalone treatment. It remains effective indefinitely as long as it stays dry. DE is non-toxic to mammals, making it a safer option for households with small children or pets, though inhalation during application should be avoided by wearing a dust mask. It is not effective against carpenter ants that nest deep inside wood because the powder does not penetrate into gallery systems.

What Not to Do

Avoid these common mistakes that make ant problems worse:

• Do not spray trails with contact insecticide. This kills visible ants but does not affect the colony. For pharaoh ants, it triggers colony splitting.
• Do not use foggers or bug bombs. These scatter ants into new areas and contaminate surfaces without reaching nests.
• Do not seal ant entry points before baiting. Sealing entry points while the colony is active traps ants inside your walls. Bait first to eliminate the colony, then seal to prevent future entry.
• Do not clean up ant trails before placing bait. The pheromone trail guides foragers to the bait. Wiping the trail forces ants to re-scout, delaying bait uptake.

Professional Treatment Options

Professional treatment is warranted for carpenter ant infestations, pharaoh ant infestations, large or widespread colonies, and any situation where DIY baiting has not produced results within three weeks.

Inspection and Species Identification

A professional treatment begins with thorough inspection to identify the species, locate nest sites and entry points, assess colony size, and identify contributing conditions (moisture, food sources, structural vulnerabilities). For carpenter ants, the technician probes suspect wood, inspects the building exterior for foraging trails, and checks outdoor harbourage sources within range of the building. This inspection drives the treatment plan — a carpenter ant program targeting a satellite colony in a bathroom wall requires a completely different approach than a pavement ant treatment targeting foundation entry points.

Treatment Methods

Professional ant treatment typically combines several approaches. Non-repellent liquid treatments applied to the building perimeter create a transfer zone — ants walk through the treated area and carry the active ingredient back to the nest, creating a colony-wide lethal effect. For carpenter ants, direct nest injection delivers insecticide into the gallery system through small holes drilled into the wall at identified nest locations. Professional-grade gel baits are placed in harbourage areas and along trails. Dust formulations may be injected into wall voids and attic spaces where ants are active. Under Ontario's Pesticides Act, all commercial pesticide application must be performed by licensed professionals holding Operator and Exterminator Licences.

Follow-Up and Monitoring

Most professional ant treatment programs include at least one follow-up visit, typically two to four weeks after the initial treatment. The technician inspects for continued activity, refreshes bait placements, and assesses whether the colony has been eliminated or requires additional treatment. For carpenter ants, follow-up monitoring over several months is recommended because satellite colonies deeper in the structure may not be fully affected by the initial treatment. Request a written guarantee from your pest control provider — most reputable companies guarantee their work for 60 to 90 days and will retreat at no additional charge if ants return within that period.

Choosing a Licensed Pest Control Company

Under Ontario's Pesticides Act, pest control operators must hold valid Operator Licences and individual technicians must carry Exterminator Licences. Before hiring a company for ant treatment, verify their licensing, ask about their experience with the specific ant species you are dealing with, and request a written treatment plan. Companies experienced with carpenter ants should describe a multi-step approach that includes inspection, nest location, direct treatment, perimeter barrier, and follow-up monitoring — not just a one-time spray. Ask whether they offer a guarantee and what it covers. For complex carpenter ant situations where multiple satellite colonies or significant structural damage is involved, choose a company that can coordinate both pest elimination and recommendations for moisture repair and structural assessment.

Seasonal Ant Patterns in Ontario

Ontario's climate drives distinct seasonal patterns in ant behaviour. Understanding these patterns helps you time prevention and treatment for maximum effectiveness.

Spring: Colony Activation and Swarming

Spring is peak ant season in Ontario. As temperatures rise above 10°C in April and May, overwintering ant colonies activate. Foraging begins in earnest, and homeowners start seeing ant trails indoors as scouts discover food sources in kitchens and pantries. Carpenter ant swarmers (large winged ants) emerge from mature colonies between May and July, often appearing at windows, in bathrooms, or near exterior doors. Finding winged carpenter ants indoors in spring is the strongest indicator of an established colony inside the building. Pavement ants that overwintered beneath foundations also become active, sending foragers into ground-floor rooms. Spring is the ideal time for preventive perimeter treatment and for bait placement to catch colonies early before populations peak.

Summer: Peak Activity

June through August represents peak ant activity across all species. Colony populations are at maximum size, foraging is most aggressive, and new satellite colonies may be establishing. Carpenter ant damage accelerates during warm months because the colony is working at full capacity. Citronella ant swarmers may appear indoors in mid to late summer, sometimes in alarming numbers emerging from beneath basement floor slabs. Odorous house ants and pavement ants maintain heavy foraging trails to any available food sources. This is the window when professional treatment achieves the strongest results because active foraging ensures maximum bait uptake and transfer within colonies.

Fall: Preparation for Winter

As temperatures cool in September and October, pavement ants begin seeking indoor shelter, moving colonies beneath heated foundations and into basement wall voids. Carpenter ant activity slows but satellite colonies inside heated buildings remain active year-round. Fall is a critical prevention window — sealing entry points and applying perimeter treatment in September and October prevents the wave of ants seeking winter shelter. Remove outdoor harbourage (firewood stacks, leaf piles, dead stumps) from the building perimeter before freeze-up to reduce the ant population overwinting near your home.

Winter: Reduced but Not Absent

Most outdoor ant activity ceases during Ontario winters. However, colonies established inside heated buildings — particularly pavement ants and carpenter ants with satellite nests in wall voids — remain active year-round. Finding ants indoors during winter confirms that a colony is living inside your building structure, not just entering from outside. Winter ant sightings should be addressed promptly because the colony will expand rapidly when spring warmth accelerates reproduction. Pavement ants are particularly common indoor pests during January and February in Ontario — they migrate beneath heated foundations and into basement-level wall cavities, sending foragers into ground-floor kitchens. If you see small black ants in your kitchen during the depths of an Ontario winter, pavement ants living beneath your foundation are the most likely explanation.

Sealing Entry Points

Physical exclusion prevents ants from entering your home and is a necessary complement to treatment. Killing the current colony without sealing entry points allows new colonies to establish through the same pathways.

Common Entry Points

Ants enter through surprisingly small gaps. Inspect and seal these locations:

• Foundation cracks and mortar joints where the foundation meets the sill plate
• Gaps around utility penetrations (gas lines, water pipes, electrical conduits, cable lines)
• Spaces beneath and around exterior doors and window frames
• Expansion joints in concrete slabs and where concrete meets the foundation wall
• Where siding meets the foundation, trim, or window/door casings
• Vent openings for dryer exhaust, bathroom fans, and range hoods
• Gaps where deck or porch structures attach to the building

Use silicone caulk for most gaps. For larger openings, use copper mesh or hardware cloth backed with caulk. Expanding foam fills larger voids but should be covered with caulk for a finished seal because some ant species can chew through uncured foam. Pay particular attention to the sill plate junction — the area where the foundation wall meets the wooden framing of the house. In many Ontario homes, this junction has gaps that are invisible from outside but provide direct access for ants from beneath the siding into the wall cavity. Inspect from inside the basement by looking at the top of the foundation wall where the wood framing sits on it. Seal any visible gaps with caulk.

Timing Exclusion Work

Do not seal entry points while an active colony is foraging through them. Sealing traps ants inside your walls and cuts off their access to bait you have placed indoors. Bait first, wait until ant activity has ceased (typically two to three weeks for successful baiting), then seal entry points to prevent recolonisation. For carpenter ants, sealing should follow professional treatment and confirmation that the colony has been eliminated. The exception is gaps that ants are not currently using — seal those immediately as preventive exclusion. In Ontario, the best time for comprehensive exclusion work is late fall after treatment has resolved the current infestation and before the next season's colonies begin scouting for new nesting sites in spring.

Kitchen and Food Management

Ants enter homes because they find food and water. Removing these attractants is as important as any treatment method and is the foundation of long-term ant prevention.

Food Source Elimination

Clean up crumbs and food residues immediately after every meal. Wipe countertops, stovetops, and tables with a damp cloth. Sweep or vacuum kitchen floors daily. Store all dry food (sugar, flour, cereal, crackers, pet food) in sealed glass or hard plastic containers — not in original cardboard or paper packaging. Do not leave fruit, bread, or baked goods uncovered on countertops. Remove pet food bowls after feeding time rather than leaving them accessible overnight. Clean grease buildup on stovetops and range hoods — grease is a powerful attractant for many ant species. Empty kitchen garbage daily and keep the bin in a container with a tight-fitting lid.

Water Source Elimination

Fix leaking pipes under sinks and behind appliances. Repair dripping faucets. Dry sinks and countertops before bed. Empty plant saucers of standing water. Address condensation on cold water pipes by insulating them. For carpenter ant prevention, moisture control is especially critical: repair any water damage promptly, ensure proper drainage away from the foundation, maintain gutters and downspouts, and ventilate damp basements. Carpenter ants follow moisture — eliminating water problems eliminates the primary condition that makes your home attractive to them.

Cleaning Ant Trails After Treatment

After your bait treatment has successfully eliminated the colony (typically two to three weeks after ant activity stops), clean surfaces where ant trails were present with a vinegar and water solution or soapy water to remove the pheromone trail residues. These invisible chemical trails persist on surfaces and can attract new ant colonies that happen to encounter them. Scrub baseboards, countertop edges, window sills, and floor areas where trails were established. Pay particular attention to the areas around entry points — residual pheromone trails near gaps in the foundation or wall can guide new scouts from outdoor colonies directly to food sources that the previous colony had already mapped.

Long-Term Prevention Strategies

Ongoing prevention is far more cost-effective than repeated reactive treatment. These strategies reduce the likelihood of ant reinfestation after the current problem is resolved.

Outdoor Harbourage Removal

Carpenter ant parent colonies typically nest outdoors within 30 to 100 metres of the home. Reducing outdoor harbourage directly reduces the ant population near your building. Remove dead trees, stumps, and rotting fence posts from your property. Store firewood at least 6 metres from the house and elevated off the ground on a rack. Clear leaf litter, mulch, and debris from the foundation perimeter — maintain a 15 to 30 centimetre gap between any organic material and the foundation wall. Trim tree branches and shrubs away from the building so they do not touch the exterior walls or roof — ants use branches as bridges to bypass foundation-level barriers.

Foundation and Perimeter Maintenance

Inspect the building perimeter in spring and fall. Seal new cracks in the foundation. Replace deteriorated caulk around windows and doors. Ensure door sweeps and weatherstripping are intact on all exterior doors. Check that all exterior vents have intact, tight-fitting covers. Address grading issues that direct water toward the foundation rather than away from it. In Ontario, the freeze-thaw cycle creates new foundation cracks every spring — make spring perimeter inspection a routine annual task.

Annual Professional Inspection

For homes in wooded areas, homes with a history of carpenter ant problems, or older homes with known moisture issues, an annual professional inspection provides early detection before small problems become expensive infestations. A technician can identify carpenter ant activity, moisture conditions that attract them, and structural vulnerabilities that provide entry — catching problems at the earliest stage when treatment is simplest and least expensive. Some pest control companies offer annual prevention programs that include inspection, perimeter barrier treatment, and guaranteed response if ants appear between visits.

Landscaping and Property Management

Your landscaping directly affects ant pressure on the building. Mulch beds against the foundation create ideal ant habitat — the moisture and organic material attract carpenter ants, and the proximity to the building provides an easy bridge into the structure. Maintain a 30-centimetre mulch-free zone against the foundation, using gravel or stone in this buffer area instead. Ensure sprinkler systems do not wet the building's foundation walls or siding — the moisture attracts carpenter ants and accelerates the wood deterioration they exploit. Address any landscape drainage that directs water toward the foundation rather than away from it. Keep compost bins well away from the building. Inspect any garden structures (sheds, gazebos, pergolas, raised beds with wood frames) for ant activity annually — these structures often host carpenter ant colonies that then expand into the main building.

Ontario Treatment Costs

Cost by Species and Situation

For comprehensive pest control pricing across all service types, see our Ontario pest control cost guide. For carpenter ant-specific service information, see our carpenter ant control page.

DIY vs Professional Cost

DIY borax bait materials cost under $10. Commercial gel baits cost $10 to $30 per tube. For small infestations of sugar-feeding species, DIY is a reasonable and cost-effective first approach. For carpenter ants, pharaoh ants, or any infestation that has not responded to three weeks of DIY baiting, professional treatment provides better long-term value. The cost of a delayed carpenter ant treatment — when structural damage has progressed from minor gallery work to compromised framing — far exceeds the cost of prompt professional intervention.

When Professional Treatment Pays for Itself

Professional treatment is not just a premium service — in many ant situations, it actually costs less than failed DIY attempts followed by the eventual professional call. Carpenter ant damage left untreated for a year can cost $2,000 to $5,000 or more in structural repairs, compared to $300 to $800 for prompt professional treatment. Pharaoh ant colonies that split after being sprayed with over-the-counter product can expand from one location to five or six locations throughout a building, multiplying the eventual treatment cost. Even for less destructive species like pavement ants, repeated purchasing of consumer bait products that fail to reach the nest due to incorrect placement can cost more over a few months than a single professional visit that resolves the problem completely. The key factors that make professional treatment worthwhile are: species requiring specialised treatment (carpenter ants, pharaoh ants), infestations in inaccessible locations (wall voids, attic spaces), building-wide problems in multi-unit properties, and any situation where DIY has been attempted for three weeks without a clear reduction in activity.

Frequently Asked Questions