Finding and treating carpenter ant nests in porch columns, sills and leaky roof edges on older east-side houses.
Fastest: call (855) 974-4733. Or send this and we call you back.
Indianapolis Pest Control arranges carpenter ant control for Indianapolis homes, especially older houses in Irvington, Woodruff Place and Cottage Home where porches, sills and roof edges have stayed wet. A local technician tracks the ants to the nest, treats it and the colony outside, and points out the damp wood that drew them in. Same-day service when available.
Carpenter ants do not eat wood. They chew nesting galleries into wood that moisture has already softened, and the east side of Indianapolis has a lot of it: porch columns that wick water up from the floor, sills under old storm windows, the box gutters built into many Victorian cornices, and floor framing under a bathroom with a slow leak. Big black ants walking the kitchen after dark are often the first clue.
The fix has two parts. A technician finds and treats the nest, along with the colony it came from, which often lives in a shade tree, stump or firewood pile in the yard. Then the wet wood has to be dealt with, because ants will move back into it if it stays soft. You approve the price before treatment and get a written report that marks where the damage and moisture are.
Craftsman bungalows and Foursquares are not immune either. Their wide porch roofs, tapered columns on brick piers and exposed rafter tails all catch water, and a few wet springs in a row are enough to start the trouble.
Black carpenter ants, the common species around Indianapolis, are large, mostly black and come in mixed sizes, from about a quarter inch to half an inch. Seen from the side, the back is evenly rounded, and there is a single bump at the waist. They forage mostly at night and leave sawdust-like frass near their nests.
Workers in one colony range from small to large, which sets them apart from other dark ants that all look the same size. Pavement ants are much smaller and brown to black, and odorous house ants are tiny and smell like coconut when crushed. For those, see ant control.
Frass is the giveaway. It looks like coarse sawdust or pencil shavings and often holds bits of dead ants and other insects. Termites never push wood out like that, and their tunnels are lined with mud, while carpenter ant galleries are smooth and clean.
Porches stay wet. Floors collect rain and snowmelt, column bases sit in that water, and porch roofs on older houses often leak where they meet the main wall. Once wood stays damp long enough to soften, carpenter ants can tunnel it with ease. Deep porches on Irvington Queen Annes and Foursquares are a frequent nesting spot.
The hollow, built-up columns on many east-side porches are a special case. Water gets in at the base or the cap, rots the core, and ants nest there out of sight. A dull, soft sound when you tap a column, or frass piled at its base, is a reason to have it checked.
Other wet spots worth watching include box gutters built into the cornice, sills under old storm windows, the rim joist below a leaky door threshold, and bathroom floors where tile has cracked. Before changing visible exterior features in a historic district, check with the IHPC.
Usually not as fast, but they can do real damage over the years. Carpenter ants dig out wood for nesting rather than eating it, and they prefer wood that moisture has already softened. A nest left alone for years can still weaken a sill, porch beam or joist, so the leak and the damaged wood both need attention.
Eastern subterranean termites are the bigger structural threat in central Indiana, because they eat sound wood as well as wet wood and can work unseen for a long time. If you are not sure which insect you have, a termite inspection settles it.
Both are wood-destroying insects, and a wood-destroying insect (WDI) report for your lender or buyer can note carpenter ant evidence along with termites. If you are selling an older house, it pays to treat and repair before the inspection rather than after.
Carpenter ants active indoors during a cold snap usually have a nest inside the heated part of the house, not out in the yard. Outdoor colonies go dormant once temperatures drop. Winged swarmers indoors in late winter or early spring point the same way: a mature colony is living in your walls or framing.
Look near warm, damp spots: around the chimney, along a bathroom or kitchen wall, near the water heater, or under a window that has leaked for years. Jot down where and when you see ants. That log helps the technician find the nest quickly.
Spring and summer change the picture. A few large ants wandering in from the yard may be foragers from an outdoor nest, which is why an inspection should come before any decision about how much indoor work is needed.
Dry the wood and take away the bridges. Fix roof, gutter and porch leaks, replace soft wood after treatment, trim branches back from the roof and siding, and keep firewood off the porch and away from the walls. Treatment removes the colony, but wet wood left in place invites the next one.
Gutters packed with maple seeds and oak leaves overflow onto fascia boards and porch roofs, so cleaning them in late fall and again in spring helps. Run downspouts away from porch footings and brick piers. Inside, fix sweating pipes and failed caulk around tubs and showers.
After a big repair, ask the carpenter to replace damaged pieces with sound wood and prime the cut ends. The technician's report gives them a map of where the ants were working.
Do not drill into walls or porch columns and spray store-bought products inside. Repellent sprays can push the ants into new parts of the house, and drilling can hit wiring or pipes. Never pour gasoline, kerosene or other fuel into a tree cavity or nest.
The technician checks porches, sills, roof edges, bathrooms and the basement for frass, trails and moisture, and often watches trails at dusk or uses bait to see where workers carry food.
You hear the cost and what is included, including any follow-up visit, before any product is used.
Where the nest can be reached, it is treated directly, with dust or foam worked into galleries and wall voids through small holes when needed. Pet and family precautions are explained first.
Non-repellent products along the foundation, at entry points and on the trails, plus bait where it fits, carry the treatment back to the main colony outdoors.
The written service report lists what was found, what was applied and where, and flags the wet or damaged wood that needs a carpenter, roofer or gutter repair.
A smaller nest of workers and brood in a wall, porch ceiling or door frame, fed by a parent colony outside. It is the most common setup in older houses, and treating it without reaching the parent colony usually brings the ants back.
The queen's nest often sits in a hollow shade tree, an old stump, landscape timbers or a firewood stack. Treating the trails, the foundation and sometimes the tree cavity reaches it, and the tree rarely has to come down.
When ants have worked a sill, rim joist or porch beam for years, the wood may need repair or replacement after treatment. Winged ants swarming indoors in late winter are a common sign of this kind of nest, because only a mature colony produces swarmers.
Carpenter ant work costs more than a general ant visit because finding the nest takes time and some treatment goes into walls. Large porches, several additions and a lot of mature trees push the price toward the top of the range.
| Job | Typical range | What it includes |
|---|---|---|
| Carpenter ant treatment | $175–$450 | Nest, trails and foundation, with follow-up if needed |
| General ant treatment (inside + outside) | $135–$260 | If the ants turn out to be a smaller species |
| Wood-destroying insect (WDI) report for a home sale | $75–$150 | Separate inspection when buying or selling |
| Quarterly general pest plan (per visit) | $95–$155 | Ongoing perimeter coverage once the colony is gone |
Estimates for Marion County and nearby towns in 2026. Your price is explained and approved before treatment; wood repairs by a carpenter are not included.
Call any hour and explain what is going on. You get a clear price before any work starts.
Many houses in Irvington, Woodruff Place and Lockerbie Square are more than a hundred years old, with wood porches, wood sills and trim painted many times over. When paint fails, water gets in, and wood that stays damp through a wet spring becomes easy digging. The same houses usually sit under big maples, oaks and other shade trees, which are natural homes for carpenter ant colonies.
The frame worker cottages of Cottage Home and many early-1900s bungalows in Beech Grove sit on shallow foundations or crawlspaces, where sills and rim joists are close to the soil. Moisture there can feed both carpenter ants and termites, so an inspection checks for both. Brick doubles around Fountain Square often show the problem at back porches and kitchen additions instead.
Freeze-thaw cycles through a Indianapolis winter open small cracks in caulk, paint and masonry every year. By spring those openings let water and ants into porch framing and window sills, which is why carpenter ant activity in older houses tends to show up between March and June.
Colony baiting and foundation treatment for odorous house ants, pavement ants and spring basement swarms on the east side.
Termite inspections and wood-destroying insect reports for east-side Indianapolis homes, home sales and closings.
Liquid and bait termite treatment for east-side Indianapolis homes, matched to your foundation and the colony's activity.
Quarterly or one-time pest control for east-side Indianapolis homes, from Irvington basements to Cumberland subdivisions.
Not sure if you're covered? Check your ZIP code.
Central Indiana has one termite that matters: the eastern subterranean termite, which nests in soil and reaches wood through mud tubes.
Not necessarily. Many nests sit in a small patch of soft wood, such as one column base or a section of sill, which a carpenter can replace after treatment. The technician's report notes where the ants were working so a contractor can judge how much wood is actually damaged.
It may hold the parent colony, but it rarely has to come down. Trimming limbs so they do not touch the roof or siding cuts off the ants' bridge to the house, and the colony can often be reached through the trails and the tree cavity. An arborist can tell you whether the tree itself is still sound.
Activity should drop sharply within a couple of weeks and stop over the following month or so. No new frass, no night trails and no indoor swarmers next spring are good signs. If you see any of those, call; a second nest or an untreated outdoor colony is the usual reason.
For the first visit, yes, because the inspection covers the basement, attic access, bathrooms and any rooms where you have seen ants. Outdoor follow-ups can often be done while you are out if gates are open and pets are inside. Mention any rooms with fragile plaster or original woodwork.
Yes, though less often. Newer homes in Franklin Township, Cumberland and Fishers usually get carpenter ants where moisture has built up: a leaky window, a deck ledger board, landscape timbers or a damp attic around a bathroom vent. The fix is the same: find the nest, treat it and dry the wood.
Yes. Ask on the phone when you call, before anything is scheduled. In Indiana, a business that applies pesticides to other people's property for hire needs a pesticide business license from the Office of Indiana State Chemist, and its certified applicators must keep up continuing certification hours.