Wasps prefer dark, dry and sheltered places to build their nests - also close to humans. Lofts meet these conditions perfectly. If you don't want a wasp colony under your roof, you should make it difficult for the animals to access it.
Wasps can cause damage under roof tiles
What makes house roofs so interesting for wasps
When we talk about wasps that like to nest under our roofs, we are primarily talking about only two species of short-headed wasps, namely the German and the common wasp. These species belong to the social, i.e. colony-forming, wasps. Of all socially living species, they are also by far the largest colonies - with around 7000 individuals. That's a powerful number, and all the more formidable given the species' fondness for nesting in close proximity to humans.
What do German and common wasps like about us humans? There are several reasons. Especially beneficial ones like:
- Human homes provide many ideal nesting sites
- With humans, there are always plenty of treats to be scooped up
The many other wasp species less known to most laypeople could also enjoy these advantages, but are too shy. German and common wasps, on the other hand, are notorious for not being shy about demanding their share of cake, ice cream or cold cuts, especially at the dining table in the garden.
Cozy nesting under the roof
They are also not timid when it comes to nesting. If you can get access to a dark, dry attic, don't hesitate. Right at the top under the ridge of the roof, young queens find ideal conditions for laying their nests in spring. Of course, it is particularly inviting when the roof truss consists of older wooden beams - because the wasp can easily gnaw off their already rotten surfaces and does not have to fly out to procure building materials.
Identify weak points on the roof
Older houses in particular are therefore popular nesting site candidates for wasps. This is also because they tend to offer more access. Wasps can easily slip under unevenly staggered or damaged roof tiles and through cracks in the mortar. If you want to prevent wasps from nesting in your attic, it is advisable to identify and eliminate such weak points. It is best to do this as early as possible, i.e. before the young queens start building their nests in spring.
When closing off possible entry points on the roof, simply arm yourself with mortar made of sand, water and cement and a spatula. You can use it to easily fill smaller gaps between individual roof tiles. If possible, you should replace damaged bricks that are completely broken. Bricks that appear porous should also be strengthened as a preventative measure by treating them with deep primer. In the case of larger gaps, it is advisable to incorporate glass fiber fleece into the mortar mass.
Also examine the masonry under the roof for possible weak points.
You should treat the wooden beams of the roof truss with an environmentally friendly wood preservative glaze, especially if it is already older.