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"Always be yourself -- unless you can be BATMAN -- then always be BATMAN."

Bat Houses.


Bat house
2001 "Bat House"

In the fall of 2001 we were renting out the farm house. Bats had become such a problem in the attic and walls that the guano was starting to seep through the plaster in the upstairs bedrooms. Something had to be done so we called the "bat man".

First thing the Bat Man did was to locate and block all the holes where the bats were getting in to the house. These were attic vents with broken or rusted out screens, gaps in the siding and sofits, loose shingles, etc. He installed one-way valves on the main exit points so the bats could easily get out but not return.

After a couple weeks, he came back to verify all the bats were gone. Then he got a 20 yard dumpster and with a giant vacuume system he sucked out all the old insulation and guano. This filled half the dumpster. It was amazing (and gross) how much bat poop had accumulated over the years.

I know there were a lot of bats because my mother would sit and count them -- when she lived there -- and from just one side of the house there would be well over 100 of bats.

Bat houses
Bat houses on corn crib.


May 15, 2002: I hung 8 bat houses on an old corn crib at the farm. I built all of these houses because I felt guilty about evicting all the bats from the farm house. There were hundreds in that house and I thought these houses would accommodate most of them.

I built these houses from plans I got on the internet. I used various materials I had lying around the shop but they were mostly built to plan.

Over the years I looked up at these occasionally but I never really paid any attention to whether bats were actually living in them. I thought I saw some guano on the ground below a couple of them but couldn't be sure.

Two years ago I took down two of the houses that had rotten roofs and it looked like one had been occupied by bats. The other was full of wasp nests and was pretty rotten so I couldn't really tell.


Occupied Bat Houses
Old Bat Houses - in use 2016

I've always wondered if any bats were in those houses. So on the evening of August 18, 2016 I made a cup of tea, set up a chair, and I sat and watched.

So just at dusk, within a 15 minute period, 13 bats flew out of three of the houses. (3, 9, 1 respectively).

It was quite a show.

Mesh bags from Walmart
Bat houses on corn crib

All remaining bat houses on corn crib in 2016. The bats that I saw on that evening, came out of the first three houses counting from the right.

i watched the next night as well but didn't see any bats. Maybe I missed them. Maybe they were finished with the houses for the season. Either way, this inspired me to pay closser attention to these houses in the future.

I will give them a once over ASAP - checking for air leaks, rotten roofs, wasp nests, etc.

2016 -- Time to build some new bat houses...

2016 Bat House
4-Chamber bat house - 2016

First more of the same...

Now that I know that these houses really work and since some of them are showing signs of their age, I think it's time to build some new houses.

This house is the same style as the old houses but it's a couple inches smaller than the specs due to the use of boards that I had on hand. It still has 4 chambers and all surfaces were scored with a skill saw in a random pattern.

This scoring was a lot of work and it seemed a bit haphazard so I made a table saw jig to use on subsequent houses (see Rocket Bat House).

2016 Bat House
Rocket Bat House

Then something new - A Rocket Bat House.

This is a two chamber 'rocket' bat house. I found this design - and the plans - on line from Bat Conservation International (

I followed the plans except for the top. I think that something that's called a Rocket should have a pointy top. So I made a pyramid roof and adjusted the chambers accordingly so that they would all contact the roof in their concentric positions.

Click here for more details on the Rocket House.

August 2022: Bat House update:

Bat houses.
Bat houses mounted on old corn crib.

The Bats Return.

Late last fall (2021) we removed all but one of the bat houses mounted on this corn crib -- four of the old houses needed repairs. One was still in pretty good shape and remains -- the largest house in the picture.

The smaller house on the left I built two years ago and I had it hung behind the Sumac tree on the right. I think it was gettig too much shade and hadn't attracted any bats so I moved it to it's new location (on the left in the picture).

Click on images to enlarge

We counted 50 bats.

On the evenings of August 3 and August 4, we counted 50 bats from the 'new' house on the left. We're pretty sure a few came from the middle house as well.

The small house on the right is a from a kit and it's only been up one season. This may not be enough time for the bats to accept it.

This was the first time in many years that we've seen bats in these houses. I was beginning to fear that bats were no longer around so it was a great relief to see them.

Click on video to the right to watch bats fly out.

Watching a few of the bats fly out.

September 2022: Making More Room for Bats Next Year

Repaired Bat houses.
Refurbished Bat Houses ready to deploy.

Refurbishing the old bat houses.

The roofs on these old houses was mostly rotted and unusable. A couple had rotted fronts and some had missing inside partitions.

When I built these, I tried out some inovations to the landing zone and the back wall. One had wire mesh screen and two had roofing material (with rocks). I thought these would work as well as surface grooves cut in the face of the plywood.

I was wrong!

Click on images to enlarge

New collection of bat houses.

I replaced the roofs with 1" White Oak -- well seasoned and weathered.

I replaced the rotted fronts. I replaced the back pannels that have the landing strip. I cut grooves horizontal grooves in these pannel spaced 1" apart all the way to the top.

I also cut grooves in the chamber pannels to help the bats move around inside the house.

Click on images to enlarge.

Bat houses.
All ready for bats to move in.