Introduction
- Project description
- A redundant timber-framed barn was converted into a residential dwelling, with a ceiling inserted at tie beam level. Although a loft space was integrated into the conversion, this was not part of a site-wide mitigation program as no EPS licence was obtained. This case study presents the findings of post-development monitoring work at a site where a brown long-eared maternity colony returned despite the absence of any specific mitigation.
- Ecologist’s name and contact details
- Patty Briggs
- Planning authority
- Dacorum Borough Council
- Brief site description
- A small, three-bay redundant listed timber framed barn within an area of open farm fields and woodland.
Pre-works roost structure
- Type of structure
- Building
- Use
- Agricultural Building
- Condition
- Derelict
- Approx. age
- 18th century
- Main construction material of walls
- Timber
- Roof design
- Pitched Roof
- Roof material
- Clay Tiled
- Internal roof structure
- Timber Frame
Pre-works roost description
- Species
- Brown long-eared bat
- Number of bats max count
- 25
- Type of roost
- Maternity Roost
- Evidence of bats
- Droppings Visual
- Roost location
- Other
- Aspect of roost
- Other
- Height of roost entrance (m)
- Not known
- Roost material(s)
-
- Nearest commuting feature
- Hedge
- Distance to nearest commuting feature (m)
- Not known
Proposed works
- Description of works
- A redundant timber-framed barn was converted into a residential dwelling with a ceiling inserted at tie beam level. Although a loft space was integrated into the conversion, this was not part of a site-wide mitigation program as no EPS licence was obtained. This case study presents the findings of post-development monitoring work at a site where a brown long-eared maternity colony returned despite the absence of any specific mitigation.
The roof space height was 3m with a width of 5.5m and length of 11m. This provided a roof space with a volume of 90.75m cubed. Traditional tiles with conventional bituminous roofing felt were used.
- Type of impact upon the roost
- Disturbance
Monitoring data
- Length of monitoring proposed
- None proposed
- Frequency of monitoring
- Single monitoring inspection completed.
- Type of monitoring
- Roost Inspection
- Evidence recorded
- Visual count of bats was 20 brown long-eared bats.
- Interventions made
- None reported
Final details
- Lessons learned
- This conversion should never have been carried out without consultation with the SNCO. The work should have been carefully programmed to avoid sensitive periods of the year. This could possibly have affected the colony size. The work should have been supervised. This conversion took place before the introduction of EPS licenses which would have addressed all these issues.
The bats had access to a large, warm, dark loft space. It is unusual for Planning Authorities to allow a ceiling to be inserted at tie beam level throughout the whole barn. This would not usually be allowed in a listed barn.
Conversion of a barn into a residential dwelling done without any prior bat survey work. It was only by luck that the design of the conversion retained a large loft area that bats could access at a gable end.
