Garden Bat Box




"Bats signify a healthy green garden" Help out with the preservation of bats with this bat box capable of housing 50 bats, that can be made in just over an hour.

Just before mothers day, I had a little spare time to cobble together a nice little bat box for my mother who had been pestering the whole family to get her one.

There are 18 bat species here in the UK all of them are endangered; they are no bigger than the size of your hand, the largest is about the same size as a Walnut.

So with a little spare time, some scrap wood recycled from an old desk (in my case), you can make yourself a nice professional bat box that looks just like an expensive store bought one.

Important Stuff
Law protects bats and their roosts, it is illegal to kill, injure or take a wild bat, or intentionally or recklessly damage, destroy or obstruct access to a bat roost.
This Instructable uses power tools that can seriously injure, maim and even kill if handled with stupidity.

First I'd like to say thanks to those who commented, oh and the feature.
I'll be making a new bat box later next month, probably with a new design as I like to do stuff like that.
Other than that I'll try and upload my instructions for my DIY Telescope/Microscope compact camera holder.


Step 1: Things You Will Need

Tools and Machinery
Crosscut / Mitre Saw (Crosscut recommended)
Drill Press
Table or band saw
Nail Punch
Set square
Pencil & rubber
Staple gun

If your shed is anything like my dad's you'll probably find everything there

Note: When I do measurements I usually do it in millimetres in the following format Length 1 x Length 2 x Depth
So 20 x 120 x 2cm would be 20cm by 120cm with a thickness of 2cm.

Untreated Wood: 20 x 120 x 2cm (No excuses! Has to be untreated! )
Nails (thin but long ones)
Clout Nails (Pictured)
Odourless Glue (No excuses! Has to be Odourless! )
Staples (optional)
Netting (optional)

Step 2: Cut the Wood Into the Required Pieces

Make sure that the wood is square with the plane or by trimming it with a table mounted circular saw.

Using the table mounted circular saw Cut the wood into these pieces:
20x34cm Sides
20x40cm Roof
15x33cm Back board
23x15cm Door

Keep any scrap wood left over for the doorstops.

Then cut the 20x34cm piece from one corner to the other, so you get two triangles, these will be the sides of the bat box.

Step 3: More Cuts

Now comes the tricky part.

Part 1
With your crosscut saw set the tilt of the head to approximately 62% and cut tightly along the length (top part of the image i.e. where 40cm is).
This will make the roof flush with the backboard and will give a nice roof over the bats' heads.

Part 2
This is the important part, adding the hole to the bottom of the box.
The hole has to be inbetween 15mm and 20mm wide to allow the bats in and out but to also keep the temperature regulated correctly inside.
This is where you need to mark the side pieces correctly (Remember it is easier to take away, than to put back )
Mark along to two longest sides the thickness of the wood used for the backboard and door.
Use the two pencil lines and a ruler to find where the gap of 15-20mm is between the pencil lines, mark that up and cut along the dashed line.

Step 4: Making the Ladder

Bats aren't like birds they can't enter though a hole in the front, nor can they fly up into the bottom like a house martin; they need to land on a ladder (or landing pad) and then climb their way into the bat box.

This is the fun part, But remember safety first before fun (I work for TV and Films so I know what I'm talking about).

But first you need to work out how long you want your ladder, with mine I left a little bit of the back board poking out above the roof that I could use to attach to a surface.

Tilt the head of your crosscut saw back too its upright position, some where on your saw should be a depth gauge, adjust this so that the bottom of the blade reaches about half way of the depth of the backboard.
Too shallow the bats won't have much to grip on, too deep and you risk your box breaking.

Now cut little slits into the wood to make the ladder, just stopping before your roofline.

Step 5: Drilling the Pivot for the Door

The roof sits on top of the side walls, so you want your door to pivot just below this.
To ensure that your door can open, leave a little gap between the roof and door, we'll use some scrap wood to close the opening to preserve heat inside during the winter, it also works quite conveniently as a doorstop as well.

Mark out at the bottom of the side walls where you're going to put the holes for the pivot, make sure that the hole in about the centre of the thickness of the door.

Drill the hole into both parts of the wood, you want the hole to be big enough for the Clout nail to fit through but tight to let little heat escape.

Step 6: Assembly

Now to assemble your bat box, I recommend using nails and a odourless non-toxic glue (the glue has to be odourless and non-toxic ).

Add a smooth stream of glue running down an edge of the Backboard whilst it is in a vice and place the side wall on top and begin to nail it down.
Wipe any excess glue that begins to seep through the gaps.

Tip: use a nail punch to sink the nails flush with the wood.

Do the same with the other side before adding the roof on top; again with glue and nails, but put glue in-between the roof and backboard.

Step 7: Adding the Door

Put the door inside the box, align it up so that its thickness is in the centre of the holes drilled in the side walls.
Get a Clout nail and hammer it in to make a pivot.

Tip: Don't bash the Clout nails in so far that it makes it hard for you to open the door.

Next you want to put in some doorstops, preferably they should fit tightly and run around the inside parameter of the door for weather proofing.
Just use glue as its a bit difficult to nail it in.

Finally with a scrap block of wood, drill a hole through it and use another Clout nail to hammer it near the top, this will be the door knob to stop the door from just falling open.

Step 8: Finishing and Optional Stuff

Well done! You've just made yourself a bat box capable of having 50 bats roosting. But wait there's more!

If you followed this Instructable and made your own, feel free to send pictures and I'll show case them on a separate page.
Stuck, got any questions, liked it? then Comment.

Optional stuff:
Inside I added some netting to allow extra bats to live here. (picture 2)

WARNING! DO NOT paint or varnish your bat box, bats have very sensitive noses, thats why we used odourless glue.

Finding a home for your Bat box:

Now that you've finished your bat box you're probably wondering where you should put it.

Bats use hedges and wall lines to navigate, so it should be placed around there.
The box should at least be 4-5 meters above the ground in a sunny, sheltered but accessible spot.
The Bat Conversation Trust recommends at least 3 boxes for all year roosting placed facing SE, south and SW.

For more information on bats and bat boxes visit:

If you followed this Instructable and made your own, feel free to send pictures and I'll show case them on a separate page.
Stuck, got any questions, liked it? then Comment.



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    28 Discussions


    7 years ago on Step 5

    i think there may be a flaw in this design. the roof should overhang the back, instead of that vertical joint, allowing possible water penetration at that joint. you can always drill a hole for a hanging screw inside the could wrap that area with some galvanised sheet metal, if you've already made it with the above config. bat's probably won't like it if it leaks...; ^)

    2 replies

    Reply 7 years ago on Introduction

    Thanks richardsan for pointing out the potential design flaw.
    I've checked to see if it leaks by spraying it down with a hose, it seems to be water tight probably because of all that glue I used.


    Reply 7 years ago on Introduction

    that wood is gonna expand and contract quite a bit...especially over time. if the glue is stable and unmovable and the wood swells and shrinks...just saying'...
    all you'd have to do is erase that vertical line, extend that one angle line and adjust the 'how to' script and you'd have a better design by 100%...; ^)


    7 years ago on Step 5

    What is the finished size of the entrance slot (front to back, from the inside edge of the bottom of the door when closed, to the back board)?

    What is the door for? My bird houses have none.

    How do we interest bats in roosting in the box?


    1 reply

    Reply 7 years ago on Introduction

    Hi Terry the entrance slot on mine is 16mm or 5/8 of an inch, but it can range from 15mm to 20mm (2cm).

    I don't know why, but most of the bat boxes I've seen have had doors.

    Bats here eat insects, so as long as you've got a good amount of insects in your garden your ok.
    If you have a pond like I do it will probably be full of larvae that will hatch into hundreds of mosquitoes.

    Another good option is to add a small light source outside the bat box that will attract flying bugs.

    But as Gordyh suggested, rubbing bat faeces on the box is one of the best ways to get them to move in.



    7 years ago on Introduction

    To help the Bats find the house, find an existing bat roost and collect a handful of their droppings. Mix in some water and spread the mix thinly on the ladder. As mentioned in this instruct able bats have sensitive noses, they will smell the house and investigate. A friend tried this on one of the four roosts he built, and it was the first one the bats moved into.



    2 years ago

    Thanks for taking the time out to create this instructable! I shall take on this project when I finish the current instructable I am building!

    Thanks again!


    4 years ago on Introduction

    IM SO EXCITED! We just bought a house on a small Lake. Trees, Herons, Ducks, but I want some Bats in my garden!


    7 years ago on Introduction

    I love that more bat boxes are sprouting up in the DIY world. My wife and I had bats in the attic of our CO home. While we loved having the bats around, having them in the attic meant that they were leaving droppings inside a living space, and we began to see dead bat bugs in the room directly beneath where they had entered.
    We consulted a bat expert in the area, who was also an exterminator. Once we clarified that we did not want the bats exterminated, just not living in our attic, he said that he could help us seal the space up and create a one way egress for them to leave but not be able to reenter. In order to keep the bats around, I built a bat box to sit at the peak of the eave and blend with the existing facia (our HOA has very strict rules about external appearance. I decided I'd make the box blend in and not tell anyone. Probably better to discuss it with your HOA first. In the end, it turned out ok once they found out about it, but YMMV), and had to paint it to acheive this. While bats may have sensitive noses, they also want a warm place to roost. If you feel the need to paint your bat box, take it from me, it will likely turn out to still be a welcoming place. Mind, though, it may take longer for them to decide to live there.

    1 reply

    Reply 4 years ago on Introduction

    In some colder or warmer climates it is advised to paint the bat box darker for heat absorption or lighter for heat reflection, but it has to be a paint that will not interfere with the bats (obviously). But sometimes painting is needed.

    low-key lysmith

    6 years ago on Step 8

    i live in the Us in Mn any major changes i would have to make? we get mostly "little brown bats", pretty sure we are dealing with the same genus.


    7 years ago on Introduction

    Kudos to your mom for wanting to help bats. This instructable is awesome :) I couldn't build something to save my life, but think it is great.


    7 years ago on Step 8

    If you are itching to decorate the bat box, you could do wood-burning. :)

    2 replies

    Reply 7 years ago on Introduction

    Wood burning does sound like an interesting idea, but apparently you can use paints such as black to regulate the temperature.
    Another idea I would like to try is carving, sticking bark on to the box to make it blend into a tree sounds good but may prove harder for them to find.


    Reply 7 years ago on Introduction

    The guide is adamant about keeping it paint-free, though, which is why I suggested it. I wish we got bats in California (well, we do, just not where I live).


    7 years ago on Introduction

    Nice work. I've always loved bats. They really are amazing creatures.
    Have you got any moved in to your box yet? I guess you might need to wait a long time before any bats realise the box is there and ready for them?

    1 reply

    Reply 7 years ago on Introduction

    I don't think any have moved in yet, but there was one flying around my head near to where we put the box, the other night whilst I was using my telescope.