BATS IN ROOFS

 

4.3.15

What to do if you find a bat and need to move it


The two most important things to avoid are being bitten or harming the bat.


Do not touch the bat unless absolutely necessary and never with your bare hands.  Put on bite-proof gloves, not kitchen or stretch gloves. Move the bat by covering it with a small box, such as a margarine tub, and sliding a sheet of card under this to trap it. You could alternatively cover the bat in a small towel or cloth and use this to pick it up.


If the bat is found during the day, place it in a non-airtight box. Leave the bat in the box in a quiet, safe place, and provide it with water on soaked cotton wool (or from a pipette if available). At dusk, release the bat close to where it was found.


If found at or after dusk, take the bat away from the immediate building site but close to the roost, and release it by hanging it on to a wall, a tree trunk or window sill.


When releasing the bat, make sure it is active and not torpid, otherwise it cannot fly. Never drop it or throw it upwards and expect it to fly.


If you are bitten or scratched by a bat, you should immediately wash the wound with soap and water. This alone is very effective in reducing the risk of any type of infection, but you must also seek medical advice on whether additional treatment is required.

Almost all UK species have been found roosting in roofs. Any work that you carry out on roofs or in roof voids may affect bats or a bat roost. To avoid disturbance, works should only be carried out when bats are absent: in most re-roofing situations, this would be the autumn, winter or early spring months. Seek advice from Natural England. Contractors and their sub-contractors must be told if bats are known to use the roof as a roost. You should also ensure that everyone working on site knows who to tell and what to do if a bat is found.

The extract from Bats in Traditional Buildings below is the advice for roofs. Download the full document from here >


Special conditions for key areas

Roof repairs


The advice in the red boxes below is now out-of-date. 

Why has the advice changed? In this video Stacey Waring who has been researching the interaction between bats and VPMs / BRMs explains how both suffer.

Update February 2015


Natural England has changed the control of underlays and bats. In summary -


•There are no Breathable Roofing Membranes (BRM) that are considered 100% bat friendly.

•BRMs must be avoided in known bat roosts.

•When/if roofing felt is to be installed in a roof that is used by bats Natural England will specify in the licence annexed conditions that bituminous roofing felt of type F1 must be used.  Bituminous felt is dark-coloured, with a rough surface that bats can grip onto and will help maintain a suitable and safe environment for bats within the roof void/structure.  Sarking boards, as used in Scotland, may be an alternative to bituminous felt.

•BRMs are also not obligatory under any Building Regulations, which appears to be a common misunderstanding.  Ventilation, regardless of the roofing felt or BRM used, is still required (see British Standard BS 5250:2011).

•When installing roofing membranes, it is essential that bat access points are maintained and any licence application should ensure that this is clearly indicated in text and figures.


Note BRMs are also known as Vapour Permeable Membranes (VPM)

The joint publication Bats in Traditional Buildings abstracted below is now out of date in the sections outlined in red below. 


it would also be wise to consider whether VPMs / BRMs are appropriate for roof coverings which are very gappy such as Cotswold stone slates.  Even if bats are not recorded as present when roofing work is to be carried out they will be able to get in later and such underlays would then be a permanent trap for a hundred years.