Project description
Conversion of former church to office space. A brown long-eared bat maternity roost was discovered during works. Roost was retained in situ with avoidance measures implemented to prevent disturbance. Monitoring confirmed continued bat presence although with reduced numbers – possible result of extreme heatwave in summer 2022. Further monitoring anticipated.
Ecologist’s name and contact details
Ruth Woolston,, TEP - The Environment Partnership
Client’s name
Site postcode
LE18 3TD
Planning authority
Blaby District Council
Brief site description
The site comprised a former church located on Main Street in Kilby, a small Leicestershire village. The building was identified to be of stone construction with a pitched tiled roof. The building supported a roof void that spanned the length and width of the building with a peak height of 2.5-3m. The roof void was bitumen lined with a traditional wooden king post structure.
Main Street bordered the site to the northeast and rural residential development extended along Main Street. An agricultural landscape extended to the southwest of the building and surrounded the wider village of Kilby.

Pre-works roost structure

Type of structure
Not In Use
Main construction material of walls
Roof design
Pitched Roof
Roof material
Clay Tiled
Internal roof structure
Timber Frame
Lighting present on site and its proximity to the roost
Street lighting is present on main street. The nearest street light is approximately 20m north of the roost access.
Photos or annotated figures of roost structure

Pre-works roost description

Brown long-eared bat
Number of bats max count
Type of roost
Maternity Roost
Evidence of bats
Bats Recorded Emerging/Re-entering
Roost location
In Roof Void
Aspect of roost
Height of roost entrance (m)
Roost material(s)
  • Bitumen Felt
  • Timber Roof Frame
Nearest commuting feature
Distance to nearest commuting feature (m)
External temperature and humidity of roost
12-18°C (nocturnal survey temperature range)
Nearest artificial light source to roost
Streetlight 20m north (vegetation does partially screen)
Nearest artificial light source to roost commuting route
As above
Photos or annotated figures of roost

Proposed works

Description of works
The works were to facilitate a change of use and renovation works to convert the former church into office space.
The majority of works involved internal strip out and renovation works that did not directly impact the roof void. Other elements included rewiring with cables to be run through the roof void, installing a WC extraction fan into the roof void, replacing a loose roof tile, and repointing the roof verge on the south gable end.
Type of impact upon the roost

Proposed mitigations

Type of mitigation
Specific technical detail of measure
A Non-licensed Method Statement (NLMS) was produced by TEP to facilitate the immediate continuation of elements of works that would not result in any impacts (including potential disturbance) to any potential roost features identified. This involved a detailed review of the itemised works programming including all methods and equipment. A toolbox talk was delivered to all contractors as part of the NLMS prior to the recommencement of works that had been halted when bats were discovered.
TEP then completed nocturnal roost surveys to confirm the status of the roost and identify all access points being used by bats. It was determined that the remaining works could be completed without resulting in the modification of, obstruction to, or destruction of the roost. TEP instructed that the remaining works must be completed outside of the breeding season to avoid potential disturbance to bats.
TEP completed an inspection of the roof void in November 2021 and confirmed that a total of 11 (likely juvenile) brown long-eared bats had remained in the roof void but that the maternity roost had disbanded. The remining works were confirmed to require entry into the roof void for a period of no more than 2 hours to pass cables through and attach the small extractor fan unit (careful examination determined that the extractor fan would not affect the temperature or humidity of the roost). A further toolbox talk was delivered to the project electrician and remaining works were completed using precautionary working methods (time and noise limitation, red light torch, and Covid measures).
Relevant annotated figures
Roost location
In Roof Void
Aspect of roost
Roost material(s)
  • Bitumen Felt
  • Timber Roof Frame
Nearest commuting feature

Monitoring data

Length of monitoring proposed
Minimum of 2 years (currently investigating long term monitoring via the NBMP)
Frequency of monitoring
Every 12 months between June and August.
Type of monitoring
Dusk and Dawn Survey
Date and time
10th August 2022 21:30
Evidence recorded
4 brown long-eared bats recorded emerging from Access Points 1 and 2. A newly identified day roost for an individual soprano pipistrelle bat was additionally recorded (Access to roof void via vent shown on previous photos at the top of the front aspect)
Internal temperature and humidity recorded
External temperature and humidity recorded
25-22 degrees C
Interventions made
It was noted that external lighting had been fixed to the building. After a discussion, Apt-Design confirmed that they were unaware that the lighting (intended for security) had been set to remain on throughout the night. They agreed to arrange with the security firm that they would be put onto a motion sensor which would be highly unlikely to be triggered by bats.

Final details

Lessons learned
This was a fantastic exercise in finding an ideal solution to the 'problem' of finding a bat roost during works that minimised impacts (costs and delays) to the project and ensured that the maternity bat roost identified would remain in situ.

Paul and Sarah (owners of Apt-Design), and their contractors, told me that they enjoyed learning about bats via frequent communications and onsite toolbox talks, and were, as a result of this, more than happy to share their work space with the bats. Paul even came along to one of the dusk surveys with his daughter to help us count the bats out which was a new experience for them both. I would class this as a win for bat conservation!

I have since stayed in touch with Paul and Sarah and they know that they can contact me if they have any further issues or questions, and I will help in any way that I can in my capacity as a bat group committee member and carer with the Leicestershire and Rutland Bat Group.

I am hopeful that the adjustment to the external lighting (and that the extreme heatwaves seen in 2022 aren't repeated in 2023) will result in the maternity roost returning in full force this year, in which case I will look to include it with the bat groups NBMP counts.