The Norfolk Bat Group is a voluntaray wildlife conservation group focussing on the conservation of wild bats within the English county of Norfolk. The Norfolk group were first formed in 1961 and were the first of the present day ninety county based bat groups in the UK.

Site copyright The Norfolk Bat Group

Bats and Bat Boxes

Make your own bat box
Where to put your bat box
Inspecting your bat box


Many bats both in the U.K. and many other parts of the world have suffered a tremendous population decline, due to roosting space losses, feeding habitat losses, various 'pest' control measures and timber treatment in buildings.

The felling of dead, old and hollow trees along with the advent of "Dutch Elm Disease" and the hurricane of 1987 in southern Britain, has considerably reduced the availability of natural roost sites for bats. Some modern building practises and the associated building regulations implemented during extensive development and building repairs have not helped either! Bat boxes provide artificial roosts sites for bats and are important for conservation and research. They cannot however, entirely replace or substitute for natural tree holes and crevices in buildings.

In the U.K. twelve bat species have roosted in bat boxes. Six of these (Pipistrelle, Noctule, Leisler's, Natterer's, Daubenton's, and Brown long-eared bats) are said to have produced babies in them. Bat boxes are also widely used as autumn mating roosts and by individuals and groups throughout the whole year.

In order to help the future of bats in your area, you may wish to put up some bat boxes and encourage others to do likewise.

Summer boxes

The boxes should be large enough to allow a maternity colony to cluster to conserve heat to keep the babies warm. They may be used throughout the year except during periods of very cold temperatures. How to make your own Bat Box.

Other designs

The BIGGER box

The BIGGER box - such as Cambs bat group have now errected a few of these slate covered monsters.... Our BIG box some 3 feet high by 2 or so wide. This photo is of the one at Santon Downham (Forestry Com.) 7 Pips there yesterday. There is another in regular use at Ranworth Broad on the side of a house.

More Open

Some boxes have been designed that open at the sides, front or base and allow inspection with less disturbance, but may be more complicated to make.

Bat Conservation Trust Approved

In the U.K. the Royal Society for the Protection of Birds sell a Bat Conservation Trust approved bat box which you need to assemble, as it comes flat-packed.

It is however far more fun to make your own - or even design one of your own.

Cement boxes

Bat boxes made from cement and woodchips are available. They are black coloured, last much longer than timber ones, are more attractive to bats and resist gnawing by Grey squirrels, but are difficult to make, or quite expensive to purchase.

Open Slot

This is a picture of Natterers bats in an open-bottomed timber slot (pre-hibernation). These are also used by Brown Long-eared Bats.

Winter boxes

Two types of hibernation boxes can be provided. The first are the outdoor ones which need fixing to trees or buildings in sheltered locations. They need to provide insulation from cold winter temperatures. They have been made from hollowed out logs or 100mm (4-inch) thick timber or with layers of plywood interspersed with insulating material. These have been insufficiently tested in the U.K. to evaluate their full potential.

The second type is a thin box - of variable dimensions, made with a rot-resistant wood, which can be affixed near the top of a wall or near the ceiling of a damp underground tunnel or cellar. These have attracted species such as Pipistrelle, Brown Long-eared, Natterer's and Barbastelle in situations where there are suitable hibernation conditions, but a lack of crevices in which the bats can - and prefer, to hide. See also Bat Brix

Further information

An excellent booklet that covers the subject in detail is "Bat Boxes" by R E Stebbings and S T Walsh. It is available from Bat Groups of Britain.

Make your own bat box


Home-made bat boxes are usually made with 'soft wood'. No timber preservatives should be used, because these may be harmful to bats, although a dark coloured stain or thin coat of emulsion paint can help to warm a box placed in sunlight. Untreated boxes will last up to ten years.

Boxes must be rainproof and draught free, and made from a rough-sawn long-lasting timber such as Larch or Sweet Chestnut at least 25mm (one inch) thick. Assembly can be accomplished using screws, nails or waterproof glue. The lid can be snapped into a groove on the back plate or hinged and secured with wire or a hook and eye.

Materials to build a Standard U.K. Bat Box

Tools: Saw, hammer, screwdriver, pencil and tape measure.

These materials make one box: