Since bats are a protected species in the UK, you will need to keep them in mind if you are planning a building project, including the conversion, removal, and modification of buildings along with construction. In general, a bat survey is likely to be required when work is going to be carried out on a property where bats are likely to be present, including properties with traditional or stone construction, buildings that are located close to bodies of water, or buildings with exposed beams.
While a bat survey is not a legal requirement for every property, you are likely to be required to have one carried out if there is any reasonable suspicion that bats might be living there. If the building is found to have bats present, further work may be required to ensure that the bats are not harmed or disrupted throughout the process.

Why Bat Surveys are Needed?

In the UK, all bat species are protected. Bat roosts are also protected under UK legislation, whether or not the bats themselves are present at the time. It is required of local authorities to assess whether or not bats are present, and if the bats are likely to be affected by development proposals, before granting planning permission. Because of this, bat surveys, reports, and mitigation plans may be required.
You may need a bat survey before the local authority will grant planning permission on a home where bats may be present. If bats are found to be present, you will usually need to have a plan in place to protect the bats and their habitat throughout the construction work before you will be permitted to begin.
In the UK, current laws make it illegal to deliberately disturb bats, transport, possess or sell bats, or kill, capture, or cause injury to bats either intentionally or accidentally.

When to Have a Bat Survey

A bat survey can be carried out at any time of year. This is known as a Preliminary Roost Assessment and involves assessing the building for the likelihood that bats might be present, including looking for any evidence of bats such as droppings or food remains. The main aim of this survey is to determine whether or not further surveys need to be carried out to be sure whether or not there are bats present at the property.

If Your Building is Suspected to House Bats

If the Preliminary Roost Assessment determines that there is a likelihood that bats might be or have been present at the property, then a full bat survey will usually need to be carried out. A bat emergence survey is typically conducted at this stage. This survey can only be carried out between May and September, as this is when bats will be at their most active. During the survey, the building will be visited by an ecologist who will study the site to monitor the entry and exit points of the bats.
These surveys are the best way to gather further information on the species of bat that is present in the property, their population, and their location. This can then be further used to determine how the presence of bats on the site might impact the construction plans, and if the construction is going to impact the bats.

How Much Do Bat Surveys Cost?

The cost of having a bat survey conducted on a property can vary depending on several factors, including the building itself, the site, the type of building materials, and more. In general, you can expect to pay around £500 for a preliminary roost assessment and report. A bat emergency survey, report, and a mitigation plan will usually cost an additional £1000 depending on what’s needed and how many surveys are necessary after the preliminary roost assessment has been conducted.

How Long Will It Take?

The survey itself can take anything from a few hours to a few days to conduct depending on the size and condition of the building, and how obvious the bats are. Once the survey has been carried out, you will usually spend some time waiting for the reports of the bat survey to come back. This will depend on the ecologist that you use, the type of survey, and the size of the survey that has been conducted. Most of the time, a timeframe will be agreed upon at the time of the survey being carried out. Usually, you’ll only wait a few days to get your bat survey results, but this can vary depending on the workload of the surveyor.

What to Do if Bats are Found

If bats are found on the property, then there may be some work to do before you can go ahead with any construction and building work that you have been planning. If bats are present on the site and are likely to be affected by any of your development or construction plans, then you will usually need to get a European Protected Species License by applying to either Natural England or Natural Resources Wales. Applications are usually granted in no more than thirty days, and you will need to have planning permission in place for the project before applying, so bear in mind that this is a process you’ll need to make sure that you’ve allocated enough time to.
Along with this, you will not be able to get the license until you have a mitigation strategy in place to deal with the bats. For example, you may have a plan to legally encourage the bats to move to a different location through the use of bat boxes or creating a bat loft to safely move the bats away from the affected areas without causing damage or disruption to them. Your bat surveyor will be able to help you prepare for applying for the license and throughout the application process.
Since bats are a protected species in the UK, it’s illegal to start a construction or renovation project that might disturb them.