Existing Buildings
Many bats use buildings for roosting, and it is vital for the future of our bat populations that any building or maintenance work takes bats into account from the outset. 
By taking bats into account prior to starting work you will:
- Minimise any costs and delays
- Help to avoid disturbing bats or their roosts, which means you will be avoiding the risk of prosecution and helping to conserve an important protected species.
This section of the website looks at some of issues around bats and building maintenance that may be of help to the building industry and bat workers. These are all ongoing areas of work and will be regularly updated with progress. A summary of the information can be found in the Bats and Buildings leaflet at the bottom of the page.
Practical information:
- I am undertaking Building / Remedial Work
Information on the use of Pesticides / Timber Treatments - Bats and Churches
Find out about the work BCT is doing on:
Breathable Roof Membranes
Breathable roof membranes have become widely used in recent years. Although originally designed for use as part of a continuous breathable/airtight barrier, they are also used in conventional, ventilated build. There are a wide range of breathable membranes available and it has become apparent that at least some of these membranes, in certain circumstances, can be detrimental to bats, although in other cases they have been reported as appropriate for use in some roosts. BCT has been made aware that some manufacturers are reporting their products as 'bat friendly'. This has not been sanctioned by BCT or Natural England. No manufacturer has so far been forthcoming in taking ownership of this claim or substantiating the reasons for it. Further information on this would be useful.
Current situation
BCT are delighted that in a collaboration with the 'Technologies for Sustainable Built Environments (TSBE)' department of the the University of Reading we have been able to secure a doctorate student to research this matter. Stacey Waring commenced her post on 28th September 2009.
The main objective is to gain an understanding of the impacts of the use of breathable membranes on bat roosts where these occur in roofs and to disseminate the findings and recommendations as a guidance document for use by both the building industry and conservation organsiations.
The planning for this research and methods to be employed are all directly linked to the feedback that has been received from bat workers.
Cavity Wall Insulation
It is known that bats use cavity walls to roost in during all seasons. The degree of importance per species and per season is difficult to discern due to the inaccessibility of the structure. Concerns about the carbon footprint of housing stock has led to even greater emphasis on having cavity walls insulated. This has given greater importance to understanding bats' use of cavity walls and identifying suitable mitigation measures where bat roosts are present.
A questionnaire was made available to all bat workers (researchers, volunteers, consultants) on experience of bats in cavity walls and the questionnaire is still available from kgunnell@bats.org.uk
BCT has formed a positive working relationship with the National Insulation Association and a mitigation document for use by bat workers and the industry is in the final stages of preparation to the first draft for consultation. There is a final technical difficulty to overcome with regard partial fill and manufacturers have been working with BCT to overcome this. This remains unresolved.
Building Regulations
Amendments to the Building Regulations in 2006, largely driven by the need to reduce the carbon footprint of building stock, has at times come into potential conflict with bat mitigation. Questions pertaining to the Building Regulations have been collected and a document prepared, for use by the building industry and bat workers, that attempts to clarify the situation. The answers given to the questions and other technical input in the document will be verified by an expert at which stage the document, in its first draft, will go onto the website. It is anticipated that document will undergo frequent updates as more situations that require clarification become apparent and as further anticipated amendments to the regulations occur. These changes to the Building Regulations have been implemented in England, Wales, Scotland and Northern Ireland.
Demolition
BCT is aware that concerns have been rasied over the process for demolitions where they are not part of a planning application. Where this occurs an S80 demolition notice is completed by the applicant and an S81 issued by a Building Control Officer at the local authority. In most cases the S80 form supplied by the local authority does not include a question on protected species and therefore it would seem likely that in many cases the presence of bats could be overlooked.
BCT is working with the Association of Local Government Ecologists (ALGE), the Chartered Institute of Building (CIoB), CCW and others to address this matter and raise awareness of local authority duty in this situation.
