Bat roosts: use of chemical pest control products and timber treatments in or near them
Which chemicals you can use in or near a bat roost and what you need to know before you use them.
Applies to England
All bat species, their breeding sites and resting places are fully protected by law.
You may however need to use a chemical product in or near a bat roost as:
- an insecticide to control pests
- a timber treatment to protect against insects, fungal growth or weathering
You cannot use chemical products in or near a known bat roost if there are bats present. Before you start you’ll need to carry out a thorough search for any signs of bats such as fresh bat droppings. The best time to apply treatments is usually between autumn and spring.
If you’re a householder or place of worship, contact the bat advice helpline before you use a chemical product in or near a bat roost. (This is a free service for these groups.)
Using insecticides
When controlling pests using insecticides you should:
- check the list of insecticides to see which products are currently approved for the control of cluster fly, wasp, bee or hornet
- only use products listed for professional use if you have the information, instruction and training to do so
- use the listed product as directed on the packaging
- take care when treating feral bees to make sure other working bees are not harmed
Treating timber to protect against insects, fungal growth or weathering
Treating timber on site in or near a bat roost may be needed to control:
- common furniture beetle (woodworm)
- deathwatch beetle
- longhorn beetle
- dry rot
- wet rot
When treating timber:
- check the list of timber treatments to see which products are suitable for use in or near bat roosts
- only use products listed for professional use if you have the information, instruction and training to do so
- use the listed product as directed on the packaging
If your product is not listed, check if its list of active ingredients include:
- 3-iodo-2-propynyl n-butylcarbamate
- Benzalkonium chloride
- Boric acid
- Copper carbonate hydroxide
- Dichlofluanid
- Disodium octaborate
- Disodium octaborate tetrahydrate
- Flufenoxuron
- Permethrin
- Propiconazole
- Tebuconazole
If the product contains:
- only one of these active ingredients, you can use it around bat roosts but must use it as directed on the packaging
- 2 or more of these active ingredients, you should contact the manufacturer before using it (see contact details on product label)
Pre-treated timber products
You can use timber that’s pre-treated off-site because the producer injects the chemicals deep into the timber. This leaves lower concentrations on the surface which are not harmful to bats.
Pre-treated timber products are not included in the lists of insecticides and timber treatments.
You should not apply products used to pre-treat timber on-site. The active ingredients will be more concentrated on the timber surface and may be harmful to bats.
Stains and preservatives
Decorative wood finishes, like stains or wood preservative, can be used around bat roosts as long as you only use them on external timber.