Why These Rooms Get Them First
The main house usually stands on deeper foundations, with a gap or a void beneath its floors. A conservatory or a garden room often sits on a slab poured close to the surface, surrounded by patio and flower beds. Black garden ants nest in exactly that ground, so the room is built on top of their territory.
These rooms also warm up quickly. Glass roofs and walls heat the floor on a sunny day, and ants are drawn to warmth for their brood. A slab that stays warm into the evening can suit a colony living just beneath it very well.
The Joins They Use
Ants rarely come through a solid floor. They come through the places where two parts of the building meet and have moved apart slightly:
- the line where the extension wall meets the original house wall
- the base of the dwarf wall under conservatory glazing
- the threshold under bi-fold or sliding doors onto the patio
- the gap round a floor-standing radiator pipe or a drain run
- the edge of a laminate or tiled floor where the trim has lifted
Watch the room on a warm afternoon and you will usually find the ants emerging from one of these, often as a single thin line. That point, and whatever is directly outside it, is where the effort goes. If the only entry is a patio door threshold on a newer house, our page on patio doors and expansion gaps goes into that detail.
Underfloor Heating and Warm Slabs
Wet or electric underfloor heating keeps a slab warm for much of the year. Around Woodley, as anywhere, that can mean ants turning up in an extension in early spring or late autumn, when the rest of the house is quiet. It is the warmth under the room, not a sign of anything wrong with the heating.
Never drill or lift a heated floor to look for a nest. Pipes and mats run close under the surface and are easily damaged. Treatment goes at the perimeter joins and outside, where the ants actually come and go, and gel bait works well here because foragers carry it down through the crack to the colony.
The one thing to remember: the nest is under or beside the room, not in it. Spray on the tiles kills the ants on the tiles. The work is at the joins and the ground outside them.
Treatment, Price and Sealing Up Afterwards
Ant control is a fixed £240, confirmed before anything is booked. What the treatment involves in your particular room is explained before you book, so you know what goes where. Typically that is gel bait placed into cracks at the joins, out of reach, and a residual insecticide on the outside wall base and patio edges.
Anybody with a crawling baby, a dog that sleeps in the garden room or a fish tank on the side should say so at booking. Children and animals stay off treated areas until dry and for as long as you are told on the day.
Once the ants have stopped, a flexible sealant along the join between old wall and new, and a fresh bead under the door threshold, closes the easiest ways in. Seal after treatment, not before, or the foragers simply find another crack. If you cannot trace where they are coming from at all, our trail-following walk-through is the place to start.