Introduction
- Project description
- Demolition of existing residence and building replacement dwelling.
- Ecologist’s name and contact details
- Turnstone Ecology
- Planning authority
- Peak District National Park
- Brief site description
- Detached dwelling adjacent woodland.
Pre-works roost structure
- Type of structure
- Building
- Use
- Domestic Dwelling
- Condition
- Not In Use
- Main construction material of walls
- Brick
- Roof design
- Hipped
- Roof material
- Clay Tiled
- Internal roof structure
- Timber Frame
- Lighting present on site and its proximity to the roost
- Not reported
- Photos or annotated figures of roost structure
Pre-works roost description
- Species
- Brandt’s bat
- Number of bats max count
- 12
- Type of roost
- Maternity Roost
- Evidence of bats
- Bats Recorded Emerging/Re-entering
- Roost location
- Under Roof Tiles
- Aspect of roost
- W
- Height of roost entrance (m)
- 4.5
- Roost material(s)
-
- Bitumen Felt
- Clay Hanging Tiles
- Nearest commuting feature
- Woodland
- Distance to nearest commuting feature (m)
- Not reported
- Photos or annotated figures of roost
Proposed works
- Description of works
- Demolition of existing residence and building replacement dwelling.
- Type of impact upon the roost
- Long-Term Roost Modification and Roost Loss
- Relevant annotated figures
Proposed mitigations
- Type of mitigation
- Compensation
- Specific technical detail of measure
- Bat House: Objective was to move the maternity colony of Brandt's bats and day roost of Common Pipistrelles to a purpose built bat barn in a separate area of the clients land so that populations of bats could continue to use the site and so that the local and regional populations of bats were not adversely affected.
The replacement barn was constructed over winter 2012/13 and was built using as much material from the old roost as was possible without destroying the roost. This involved using wooden weatherboarding from the front of the original house, and removing the insulation from the original house and filling the new barn. The replacement barn was designed to replicate the locations bats were observed using, including; ridge tile access, raised tiles along the hipped end of the barn, lifted lead access tiles and internal beams. The aspects of each face of the barn were positioned so that the solar regime the new building was subjected to would replicate that of the original structure. Once the barn was completed and the weather was suitable the roof and ridge tiles were stripped by hand and the bitumastic lining was also removed (all tile stripping was completed by our intrepid licence holder Simon Parker who was roped to the roof).
Size: The overall dimensions of the building are 5 m x 7.5 m with a ridge height of approximately 4.25 m. The internal ridge height of the bat loft area is 2 m.
Materials: Oak main frame, softwood pressure treated internal trusses, a mixture of new and reclaimed concrete roof tiles, bitumastic lining, reclaimed wooden weatherboards from original house, lead flashing and plyboard flooring.
Additional info: The planned location for the replacement bat barn contained several small trees and was adjacent to an outgrown laid hedgerow. The small trees were removed or coppiced and the hedgerow was re-laid so that the amount of sunlight hitting the new barn was as high as possible.
- Relevant annotated figures
- Roost location
- Under Roof Tiles
- Aspect of roost
- S
- Height of roost entrance (m)
- 4.25
- Roost material(s)
-
- Bitumen Felt
- Clay Hanging Tiles
- Nearest commuting feature
- Hedge
- Distance to nearest commuting feature (m)
- Not reported
- Internal temperature and humidity of roost
- 29.5
- External temperature and humidity of roost
- 22.5
- Photos or annotated figures of roost
Actual mitigations implemented
- Type of mitigation
- Compensation
- Specific technical detail of measure
- Bat House: Objective was to move the maternity colony of Brandt's bats and day roost of Common Pipistrelles to a purpose built bat barn in a separate area of the clients land so that populations of bats could continue to use the site and so that the local and regional populations of bats were not adversely affected.
The replacement barn was constructed over winter 2012/13 and was built using as much material from the old roost as was possible without destroying the roost. This involved using wooden weatherboarding from the front of the original house, and removing the insulation from the original house and filling the new barn. The replacement barn was designed to replicate the locations bats were observed using, including; ridge tile access, raised tiles along the hipped end of the barn, lifted lead access tiles and internal beams. The aspects of each face of the barn were positioned so that the solar regime the new building was subjected to would replicate that of the original structure. Once the barn was completed and the weather was suitable the roof and ridge tiles were stripped by hand and the bitumastic lining was also removed (all tile stripping was completed by our intrepid licence holder Simon Parker who was roped to the roof).
Size: The overall dimensions of the building are 5 m x 7.5 m with a ridge height of approximately 4.25 m. The internal ridge height of the bat loft area is 2 m.
Materials: Oak main frame, softwood pressure treated internal trusses, a mixture of new and reclaimed concrete roof tiles, bitumastic lining, reclaimed wooden weatherboards from original house, lead flashing and plyboard flooring.
Additional info: The planned location for the replacement bat barn contained several small trees and was adjacent to an outgrown laid hedgerow. The small trees were removed or coppiced and the hedgerow was re-laid so that the amount of sunlight hitting the new barn was as high as possible.
- Relevant annotated figures
- Roost location
- Under Roof Tiles
- Aspect of roost
- S
- Height of roost entrance (m)
- 4.25
- Roost material(s)
-
- Bitumen Felt
- Clay Hanging Tiles
- Nearest commuting feature
- Hedge
- Distance to nearest commuting feature (m)
- Not reported
- Internal temperature and humidity of roost
- 29.5
- External temperature and humidity of roost
- 22.5
- Photos or annotated figures of roost
Monitoring data
- Length of monitoring proposed
- Not reported
- Frequency of monitoring
- Not reported
- Type of monitoring
- Dusk and Dawn Survey
- Date and time
- 1st July 2013
- Evidence recorded
- The internal walkway and beams were swept clear of bat droppings following the installation of the old insulation to allow easier identification of fresh bat droppings. Common Pipistrelle droppings were found scattered over this and a small collection of Brandt's droppings were found in one location. An emergence survey was completed in July 2013, during this at least two Brandt's bats emerged from the new bat barn (one from the south west hipped end and one from the west side of the ridge) along with an individual Common Pipistrelle which emerged from the western face of the roof.
Pipistrelle droppings were found within 4 weeks of completion of the bat barn (April 2013), Brandt's bat droppings were found on our monitoring visit which was completed in July (4 months).
- Interventions made
- Possibly add more insulation at a later date, and if temperatures are not shown to be staying high enough heating will be added in an attempt to encourage bats to breed on site once again.
Final details
- Lessons learned
- Little is known about Brandt's bats and their requirements with regards to mitigation and roost specification. This project has given an indication that replicating as many features as possible between the original roost and the replacement roost is important. This along with another project involving Brandt's roosts we have had over the last year has led to the suggestion that this species of bat is sensitive to temperature changes within a roost. Both the roosts were inhabited by people until approximately two years ago, and the evidence we found within would suggest that the roosts were previously much much larger (Oak House contained huge numbers of droppings under the ridge tiles, below lifted tiles and within the loft space - many more than the numbers of bats we found during surveys could produce even over a long time period) We were very lucky to have a willing client, an experienced architect and an excellent builder, all of whom listened to our instructions and implemented them as required.
