Wasps Going Under Roof Tiles - Does This Mean There Is a Nest?

What a Nest Looks Like From the Ground

Steady two-way traffic at one specific point. Wasps arriving from several directions, converging on the same spot, disappearing, and others emerging. It looks purposeful, and it continues all day in reasonable weather.

The rate tells you the size. A few a minute is an early or small nest; a constant stream is a mature one, and by August a mature nest holds several thousand wasps.

What Is Not a Nest

Wasps landing on the tiles and crawling about without going in. Wasps working at a fascia board or a fence panel — that is nest-building material being scraped off timber, and the nest itself may be some distance away.

A single wasp investigating a gap is also not a nest. In spring, queens explore dozens of sites before choosing one, so activity in April that stops within a few days generally means she went elsewhere.

The Tile Is a Door, Not the Nest

What you are watching is the entrance. The nest itself is almost always inside — in the roof void, in the space between the felt and the tiles, or hanging from a rafter some distance from where they go in.

That is normal and it does not complicate the job. Treatment goes to the entrance the wasps are using, and the returning wasps take it inside with them. You never need to see the nest, and no tiles need lifting.

Why Roofs Are So Popular

A roof void is dry, sheltered, warm, undisturbed and has multiple ways in at the eaves. From a wasp’s point of view there is not much better available.

Older roofs with slipped or lifted tiles and gaps at the eaves are the obvious candidates, but modern roofs get nests too — usually at the junction where an extension or bay roof meets the main wall, or through a soffit vent.

What to Do and Not Do

Do not go up a ladder to look. Do not block the gap — wasps chew an alternative route out and it is frequently into the loft and then into the house. Do not spray it from below.

Keep the loft hatch shut, keep the windows on that side closed while it is treated, and stay off that part of the garden for the rest of the day. It is £90 fixed, guaranteed, and a roof nest is a routine job.