Today we’re going to talk about bats and building work.
If you’re a homeowner planning some building work on your property, bats probably aren’t the first thing you think about.
But it's certainly something that you can’t ignore because bats have been known to hold up building projects for months!
In this post I’ll show you the rules, things to look out for, and potential solutions.
Bats and Building Work - What You Need to Know
You might be surprised to know that there are laws about bats and building work that you must consider before you make your plan of action.
The first thing you need to consider is that all types of bats are protected species in the UK.
There are 4 pieces of legislation that affect bats and building work. You can find detailed information about all of the bat protection laws here: https://www.gov.uk/guidance/bats-protection-surveys-and-licences
But here’s a summary:

Re-roofing, construction and demolition projects, and extension or conversion proposals can all affect a bat roost in a building or barn.
It's always a good idea to ask for a survey where roosts are likely if the building or barn:
- has little or no disturbance from artificial lighting
- is close to woodland or water
- has uneven roof tiles and large roof timbers
- has cracks, crevices and small openings
- has a roof that warms in the sun with a large roof space for flying
- has hanging tiles or timber cladding on south-facing walls and has not been used for several years
Now that you understand the basic rules, let’s find out how to determine if you have bats at your property.
Things You Can Look Out For (Checking for Bat Roosts)
Your first step is to check for any of the following signs:
- Bat droppings - These have a crumbly texture as opposed to mouse droppings which dry hard.
- Emergence - Look out for bats re-emerging from the roost during peak months (see calendar later in this post).
- Bat chattering - Listen closely for a high-pitched clicking sound. If there is a big enough group, you might hear a chirping sound.
- Feeding remains - Bats eat the bodies of large insects like moths and butterflies, often leaving behind the head and wings.
- Scratching and tracks - These signs are less common but still visible in some instances.
These are some of the things you can look out for yourself. But you will eventually need a professional bat survey.
If you already know you have a building with bats, then it's a good idea to consider the bats during the early planning stages of your project.
It's important to get your bat survey completed by a professional ecologist. You can search for one using the database of the Chartered Institute of Ecology and Environmental Management (CIEEM) here.
Once you’ve confirmed that you have bats at the property, it’s time to look at what you can do about it.
Next Steps
Working with your ecological consultant, there are two ways to complete your building work around bats.
- Get a bat mitigation license (if the proposal is likely to affect the bats)
- Plan building works around bat seasons
- Create access for bats
Create Access for Bats
Size
The size of the bat access point will depend on the type of bat at your property. Almost all bat species are small (with the exception of the Horseshoe bat). This means that they can land on the building and crawl into their roost.
As the exception, the larger Horseshoe bat has a wider wingspan. And they tend to fly into their roost and hang upside down. Which explains why they need a bigger roost.
Location
The location of a bat access point will depend on the building work and type of roost. Ideally, you should aim to keep the new access point as close to the the original roost as possible. Consulting with your ecologist is important here.
Products
If you need to create new access points for bats to their roost, a bat entry tile of some kind is a good option.
We've found that most renovation or conversion projects tend to be on older properties that have a slate roof. So we developed some component products for creating bat entry tiles.
These components can be found in our Bat Access Slate and our Bat Access Tile Kit.
The bat access slate comes in 2 different sizes in standard grey slate. But if you wan't to make your own, you can use the parts and instructions provided in the Bat Access Tile Kit.