Bat House Forum

[IowaNate]

  I am posting a design that I came up with to make (3) three chamber bat houses that meet Bat Conservation International's minimum requirements (14" wide and 20" tall interior dimensions). Each house should be able to accomodate at least 200 bats. The cutting diagram will follow in this post after I draw up a good copy. The materials can also be used to make two extra wide (24") houses.

Materials required

  4x8' sheet of 5/8" plywood

  1x4" 12 feet long

  1 pound of 1 5/8" exterior wood screws

  48x84" petscreening

  1000 stainless steel staples

  1 tube exterior latex caulk

  1 quart of exterior latex paint (color according to your region)

Tools required

  drill with 3/16" wood bit and phillips bit (1 1/2" hole saw optional)

  circular saw

  staple gun

If you roughen the partitions with screws or some other device instead of using petscreening and staples, you will save about $5 per house. These houses are easy to build even for someone with limited carpentry skills.

[IowaNate]

 Here is the cutting diagram to scale. B indicates the backs, F indicates the fronts, P indicates the partitions, and R indicates the roofs. The sides are designated as S on the 1x4".

 

 

[IowaNate]

  Hopefully this will help some new bat house builders to make a few economical yet well constructed bat houses that are easily capable of housing nursery colonies. For the experienced bat house builder, it shows a great way to make a few houses for your friends or for new sites in a short amount of time and at minimal cost. This is the design that I will be using in my city parks. I didn't cover many of the steps in building the houses (venting, partition grooves, or assembly), but if you need assistance or advice just send me a message here on the forum and I will respond to you within 48 hours.

                Happy bat housing to you all!

                                                                  Nate

[Terry Lobdell]

Nate, that is an excellent sketch! Thanks!

[IowaNate]

  No problem Terry. This design also doesn't require ripping the 1x4's down to make the three 3/4" chambers, the 5/8" plywood is perfect for the chamber spacing and the thickness should hold heat better than 3/8" or 1/2" plywood. Overall weight on each house should be between 15 and 20 pounds, I will get the exact weight after I build the first three.

  The Cedar Rapids Parks Dept. has been very slow at getting back to me about putting up houses at the two parks near my home. After I first spoke to them, they were very eager and wanted the bat house design and location of each pole mounted. I sent them photos of the sites and the design specs over three weeks ago and have not gotten a second response. Due to the slow response, I went ahead and emailed Pleasant Creek State Park which is a 1500 acre public area with a manmade 410 acre lake. This site is just 15 miles from my home. The lake has excellent shore fishing access thus it would be another great spot for bat houses near the waterline. Plus the lake is patrolled by the DNR at all times of the year so vandalism will hopefully not be a problem.

  Hopefully I will get the the final word on all three sites within the next few weeks so I can begin making more houses and get them hung by mid April. With this economical design, building at least a dozen houses over the course of a week shouldn't be a problem.

[IowaNate]

 Great news! Pleasant Creek State Park is managed by a woman I went to highschool with. She is more than happy to allow me to hang "as many bat houses as I deem usefull" to the park. She said that the campground at the park (which is located less than 200 yards from the water's edge of the 410 acre lake) could really use a few bat houses to help control the insect population. This lake is surrounded by roughly 40% prairie grass, 15% open manicured lawn, and 45% oak and maple woods with a few pines. On my evenings and late nights of bass and catfishing this lake I have seen hundreds of bats. I am going to do an initial hanging of six bat houses of this economical three chamber design at first. I am planning on hanging them idividually on poles facing South or Southeast and then checking what houses attract the most bats in the area. If I get a noticeable difference in bat occupation between some areas, I will hang more houses in that area. I am expecting bats in every house that I hang though.

[Terry Lobdell]

Nate, that sounds like an excellent site for little browns.........I'll bet with 6 bat houses there by mid summer you will have a lot of occupancy!

[IowaNate]

  I finally bought and cut the wood today for these houses and each house weighs 22 pounds. The total cost of the wood was only $27! $9 worth of wood for each house was less than I expected, granted the screws, screening, staples, and caulking/paint added some cost, but total cost will actually be a bit less than $20.

   Measuring and cutting the wood took me a whopping 30 minutes, and assembly for one house took about an hour and a half (minus painting).

[Terry Lobdell]

Nate that is not a bad price at all for those materials. The design is just about right.......big enough to hold a lot of bats but small enough that it can be easily mounted. Was that A/C plywood you used?

[IowaNate]

 I can't remember the exact type of plywood it was, but it was indoor/outdoor 5/8" sheathing (for subflooring and outdoor underlayering). So I had to sort through some before I found a good piece that didn't have the first layer of ply pulling away or missing in some areas of the wood. But then again, that 4'x8' sheet only cost me $14.99 at Lowes. And it is probably rough enough that if I would've cut the partitions different, I wouldn't have had to use screening for footholds. These houses should last at least 20 years with a good exterior paint job.

[Terry Lobdell]

Sounds like cdx plywood.........I've seen it rough enough to baffles also.......some of the single crevice bat houses I have mounted on my house have weathered 5/8" cdx plywood as an experiment to see if the bats would use them........usage has only been by a few bachelors..........

[IowaNate]

 Here is one of the bat houses primed and ready to be painted. A very decent house for about $20 and two hours worth of construction time.



 

[IowaNate]

 The first of this design was given to a friend in late June (and hung within a week) and he is checking for occupancy for the first time tonight. He hung it within 100 yards of the river, in full sun, no branches or obstructions within 20 feet, and 14 feet up on a pole facing South.

  I told him to first check for guano beneath the house since it is getting late in the season and the bats may have moved on. It is his first bat house and he is very excited about getting some bats in it. Hopefully he will have good news in the morning!

[IowaNate]

 The bat house is a success after only two months! My friend estimated 12 to 15 bats were in the house by looking from underneath, and there was a good sized guano pile according to him. He says he wants another house next year if the colony grows to at least 100 bats by Summer.

[Terry Lobdell]

Nate, that is great news! From the description of the guano pile, it sounds like it had a lot of bats using it!