The short answer
Leave it alone and call a pest controller. A wasp nest in an enclosed roof space is one of the few household problems where the DIY version is genuinely dangerous.
- Do not block the entrance. Blocked wasps chew their way into the house instead.
- Do not spray a nest in a roof space. In an enclosed space you provoke thousands of insects between yourself and the exit.
- Keep people and pets away from the flight path and close nearby windows.
- Call a professional. Most councils do this cheaply, and a private pest controller is usually inexpensive for a single nest.
- A nest in the open on a shed or a hedge that nobody goes near can often simply be left. Wasps abandon a nest at the end of the season and never reuse it.
What will ruin it
Multiple stings and any sting in the mouth or throat need urgent medical attention. Anyone with a known wasp allergy should not be in the building while it is treated.
Why it works
Wasps defend a nest collectively and release an alarm pheromone when threatened, which recruits the rest of the colony. That is the mechanism that makes a confined space dangerous.
Household chemicals can be dangerous in combination. Never mix them, keep the room ventilated, and test anything on a hidden patch first. Full disclaimer.
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