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How to make a bat box


Bat boxes are designed to mimic natural bat roosts. They usually consist of narrow slits that bats can crawl into. Bats don’t like draughts, so make sure all joints are secure. They also need rough-textured wood to cling onto – if you can’t find rough-sawn timber, then use the teeth of a saw on its side to create a rough surface.

How to do it

Measuring the bat box


Measure the wood. You'll need four lengths: 58cm; 30cm, 20cm and 15cm. Measure the batons – you'll need 2 x 30cm and 2 x 20cm.

Cutting the wood to size


Cut the wood, using a saw or jigsaw. Sand any rough edges to remove any splinters. Drill a hole near the top of the largest piece of wood – you’ll use this to attach it to the wall.

Nailing the batons to the plank


Leaving 10cm below the hole, nail the 30cm wooden battens to either side of the 20cm x 58cm piece of wood.

Adding the third layer


Nail the 20cm x 30cm wood on top of the 30cm batons and repeat with the 20cm baton pieces.

Adding roof flashing to protext from rain


Nail the 20cm x 20cm piece of wood to the 20cm length batons. Then attach the 15cm piece as a roof so it covers the wooden pieces completely and doesn’t allow water in. For extra weather protection, attach a piece of roof flashing to the top. Fix the box under the eaves of your house in a sunny but sheltered spot.

Our tip

Rough sawn wood is ideal for giving bats something to cling onto, but if you can't find any then roughen it with saw cuts to help them cling properly.

To give bats the chance to choose the most suitable roost for the particular time of year site three boxes in your garden facing north, south-west and south-east.

Discuss this project

Talkback: How to make a bat box
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ebbypea 24/11/2011 at 15:28

I love bats, we sit in the conservatory at night to watch the bats swooping above us. I hope i can make a good one because I will be so chuffed with myself, and hopefully it may encourage more bats in my garden. Thankyou for the tips.

Richardjulian 24/11/2011 at 15:28

do you really mean to use nails 19cms by 4 cms? Wouldn't it be easer to use smaller nails!

mikehinson 24/11/2011 at 15:28

It seems you measure 12.5cm from the top acute angle, not the bottom one, which wastes quite a lot of wood, but gives the right size opening and a smaller box...I've made 2 boxes, both ways

Richardjulian 24/11/2011 at 15:28

You need 45 or 50mm long oval wire nails not as above; Step 3: the entrance hole needs to be 15-20mm. if you cut off 12.5cms the hole will be too big and you will then need to attach a piece of plywood to reduce the size, which is what I have had to do. If you cut less off the triangles, you will not have enough wood for the front.

tim.gardener 24/11/2011 at 15:28

On it is recommended to place batboxes due South. Other sites have similar recommendations. Are you aware of this and if so, is NE, NW and SE really better?

The argument for a due South planig is that youngh bats "need warmth". The USA site even recommends painting the South facing wood in black latex.

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