Maintaining your bat box
If you wish to treat or paint a bat box to improve its longevity, you should ideally do this prior to putting the box up.
You should only paint and/or treat the exterior of the bat box. Additionally, we recommend leaving the ‘landing board’ of the box unpainted so that bats can safely land and crawl into their roost without coming in to contact with the paint or chemicals.
- Use a water-based or acrylic paint, preferably in a dark colour.
- We recommend choosing a paint that is sold as animal or pet-friendly.
- Use only a fluid containing a synthetic pyrethroid or boron compound, to treat wood-boring insect, with a copper, zinc or boron compound to prevent rot, preferably in emulsion or aqueous solution.
- Use the minimum amount of pesticide.
- Refer to table 1 of the list of products that are suitable for use in bat roosts, found on the Natural England website, by clicking the button below.
- If your product isn’t listed, check the active ingredients listed in tables 2 to 7.
- You can use the product around bat roosts if it contains only 1 active ingredient as long as you use the product as directed on the packaging.
- If the product doesn’t appear in table 1 and has 2 or more active ingredients you should contact the manufacturer before using it. See the product label for more information.
You must allow the treatment/paint to fully dry before your bat box is put up.
Future repairs, cleaning or repositioning
Once bats have moved in, a bat box can only be opened, moved or disturbed by someone with the right licence. This is the case all year round, even if the bats are only in residence for part of the year.
How do I know if my box has been used?
To check if the box is currently being used, look out for droppings and urine staining below the access point. During the summer (May to September) you can also listen for ‘chattering’ and watch the box for an hour either side of sunset to observe any bats leaving to feed.
It may be necessary to open the box to determine whether it has been used by bats. If the box needs to be opened to check it then there must be a suitably licensed bat worker present.
Sometimes, members of the local Bat Group can check if a box is in use for you and provide the advice you need. If they aren't able to help, you may need an ecological consultant.