Key Signs Of Carpenter Ants On A Property

Carpenter ants can cause serious damage to wooden structures. Although they do not eat wood, they tunnel through it to build nests. Early detection is important. Spotting the signs of carpenter ants helps you act quickly to prevent costly repairs and know when to call pest control for ants.

Piles of sawdust-like frass

One of the most obvious signs of carpenter ants is frass. This looks like fine sawdust and often appears beneath wooden beams or skirting boards. The ants push frass out of tunnels they create inside the wood. Therefore, these piles usually collect near baseboards, door frames or under loft insulation. Woodworm also create frass, so look out for other signs as well.

Large black ants indoors

Although not every ant indoors is a carpenter ant, regular sightings of large black ants may be a warning sign. Carpenter ants are larger than most common ants in the UK. They often roam at night, especially in kitchens or bathrooms. If you regularly see them along walls or floors, they could be nesting nearby.

Rustling sounds in walls

You may also hear faint rustling or clicking inside walls or ceilings. These sounds often increase at night when ants are more active. While many pests make noise, soft clicking or crackling sounds could be signs of carpenter ants tunnelling through timbers. Over time, this activity can weaken internal structures.

Damaged or hollow-sounding wood

If you tap skirting boards or beams and they sound hollow, this could be another sign. Carpenter ants remove wood to create nesting space. Although the surface may look intact, the inside may have extensive tunnelling. Eventually, this can lead to sagging floors or damaged frames. If you notice unexpected wood damage, consider a professional inspection.

Shed wings near windows

Carpenter ants produce winged reproductive ants in spring and summer. These flying ants leave the nest to start new colonies. Therefore, discarded wings on windowsills or floors may indicate their presence. You may also see the swarm itself, especially near light sources.

Outdoor nesting signs

Not all carpenter ant nests are indoors. You might spot activity around tree stumps, fence posts or log piles. If ants seem to be entering cracks in external wood, they may have formed a nest. Even if the nest is outside, the colony may expand indoors.

We understand how to confirm the signs of carpenter ants and deal with them safely. We offer professional pest control in Surrey and use safe, targeted methods that follow UK pest control regulations. If you suspect a problem, our Surrey team can inspect and advise on the best approach.