Bat House Forum

[ROB]

I am in the process of building my first bat house. I think to attach the mess or screen it would be easy just to take a thin piece of wood,  like a piece of 1/4 round moulding, and nail it at the top and bottom of the mess . It would hold it and you could use  stainless steel finishing nails and not worry about trying to staple into the plywood. You may have to pre drill a very small pilot hole so you don't split the moulding. Just my thoughts  

[RockAuto.com Auto Parts]

Framing the mesh (works better than a "mess"!) in wood strips is a good idea.  You could even run a strip of wood down the middle if your bat house is large and the mesh starts to sag outward and/or if you want to create smaller, warmer sections for the bats.  The ordinary staple gun staples I used seem to still be working fine too. 

[ROB]

I guess I need to proofread my messages before I send them.

[splaestro]

Hi folks-- excited about building my first bat house and just discovered this forum. I'm planning on building a single-chamber house as per the BHB handbook design. Had some questions about preparing the inside surface of the house: 

When testing new materials, it is best to make the partitions removable so that if the material wears out and needs replacing, the whole bat house won't have to be thrown out or torn apart to get to the inside.

Make the partitions removable by using a small cleat attached near the bottom on each side. The bottom of the partitions will rest on the cleats.
Make the cleats removable by using thumbscrews.

 
In using such a modification, should I compensate for the thickness of the partition backing by making the chamber deeper? What material do you all recommend for the partition backing?

If I were to go with the instructions as in the handbook instead, and simply make grooves on the backboard, I'm a little unclear on how much of a groove there should be. The book says 1/32 to 1/16 inch [b]deep; in terms of width, should they really just be scratches, or would actual grooves like what you'd get using a router be good?

Thanks for any and all counsel!

[Terry Lobdell]

Hi,

I use pine 3/4" boards for my partitions (baffles) most of the time. Although plywood also works well, some question the adverse effects of the glue vapors.

I have had the best luck with a finished crevice thickness of 3/4". Anything wider attracts more paper wasps.

I have always made saw kerfs either with a table saw or circular saw about 1/6th to 1/8th of an inch deep. The more the better.

The material I prefer the most right now is pet mesh. You can get it at walmart. It's just a vinyl coated fiberglass storm door screen more durable than regular fiberglass mesh. I have had very good luck with bats using houses with regular fiberglass mesh but have doubts about how long it will last.

Use stainless steel staples to attach the mesh. A staple about every inch and a half to 2 inches is about right. I have also used glue but prefer the staples because of having to wait for the glue to dry.

Joe has some good pictures on here showing how to attach pet mesh.

Hope this helps!

[Joe Spencer]

After doing so much experimenting with materials and substrates I'm currently still finding that KISS is the best way.  It is taking me so much longer to build bat houses with plywood partitions.  You need to score or modify with screening which you wrap around it and then staple and I'm finding that it isn't worth the time.  Plywood prices also have recently gone through the roof and I only use it for the house exterior. KISS is: cheap rough pine boards which require no scoring or modifications.  Cut them to width and fasten to 3/4" spacers.  The thicker wood also helps to buffer temperatures.  What you lose in roosting capacity you gain in thermal mass.  Make the partitions a separate package which is inserted into the bat house.   Lightweight mounting.  Makes for a simple good sized effective maintainable nursery house.  Kent Borcherding swears by wood even thicker and larger such as 2X roughcut lumber readily found at sawmills reasonably.  For those people that don't want or elect not to mount bat houses on a building I think a multiple chambered rocket made with the same materials is the way to go.  You could make it very attractive with a Copper flashing roof which looks great as it reacts with mother-time and oxidation.

[splaestro]

Thanks, Terry and Joe both, for your replies. KISS is always a good principle to go by, and I think for my first house I had better stick to it.

I realized after reading Terry's reply that I didn't make what I had in mind clear enough-- I'm planning on building a single-chamber house, so there won't actually be any partitions (poor choice of words on my part), just the backboard and the front cover. Reading the post from Mark K that I quoted, I was thinking that I might need to put a removable layer in against the backboard (something thin, maybe something like Masonite), to which the mesh would be attached. Hence my concern about the chamber not being deep enough... anyway, I've obviously violated the KISS principle with that line of thought.

As for kerfing, looking at Scott's bat house website http://habitat.ms11.net/bat/medhouse.htm made it clearer what I need to do, and I think I'll end up going this route.

Thanks again!

Brian

[Terry Lobdell]

Joe,

How has the rough sawn wood without saw kerfs for baffles worked so far? And what kind of lumber do you prefer?

I have used only white pine, quaking aspen and tulip poplar as they don't produce sharp splinters.

[Joe Spencer]

Terry, it seems to work fine but I really don't have enough bat houses up to compare. I'm using white pine since it is cheap in my area.  Also the wood is dried out nicely by my local mill with pine pitch not being a problem with it either. Since I haven't tried anything else I don't have a preference.  I try my best to pick out pieces which have horizontal roughage for the bat foothold.  I'm not sure if I've seen splintering as a problem.  I'm very interested in any additional info you can provide from your experience on the latter.  I'm considering making a homeade kerf table saw with multiple blades separated by washers on one drive to enable me to cut all the horizontal foothold grooves quickly in two passes.  I too favor your kerf depth of 1/6th to 1/8th.  I'm wondering though if grooves aren't overkill.  When I see how easily little brown bats are moving on plywood which has vertical grain which can be seen on the canoe creek live bat cam I'm pondering if it is worth the extra time on the rough pine which is surely far more grippable without kerf cuts than the plywood baffles lacking it. Splaestro, I'm assuming your placing the bat house on a building?  Sounds great and we'd welcome bat house photos when you complete the project! :thumbsup1:

[Terry Lobdell]

Joe, hemlock, larch and most plywoods can have some nasty splinters when they dry out.

I too would like to try a multiple kerf blade setup on my table saw but have yet to do so.

Also in the future I am going to try making bat houses out of old pallet wood. I can get the pallets free. Much of that type of wood is fairly rough and may not need kerfing at all.

[splaestro]

Yes, Joe, I'm planning on putting the completed box on the east side of our house, hence my question in a separate thread about mounting through vinyl siding.





Here are a couple of phtotos from after I completed the kerfing. I did these with a circular saw, so they're almost 1/4 inch deep. Probably not ideal, but we'll see how it goes. The first is the backboard, the second the upper front cover:






Taken with my camera phone, so not the best quality pictures.

I just finished the staining yesterday; I used MinWax water-based. Does anyone have experience with this? I'm wondering how it will hold up on the landing area once exposed to the elements. Maybe I should put a coat of polyurethane over the stain in this part? Obviously, not so much that it would fill the grooves...

Thanks again--

Brian (splaestro)

[Joe Spencer]

Ah, not bad photos considering.  As long as you don't use oil based products you're ok.   Is it exterior grade plywood? Is it going to be mounted on the gable end of the house?  If it is mounted under the eaves side, that will provide some protection if you can get it up that high. Fantastic!  Looking forward to feedback or photos after mounting.  How far are you from the nearest water source?  Have you seen bats flying in or around your property or neighborhood?

[RockAuto.com Auto Parts]

Here is a durability update! I have not touched the bat house since hanging it over four years ago. At least looking up from the ground, the latch hook rug mesh exposed below the house entrance does not look weathered or worn at all. Over the summer, my daughter and I watched bats leave the house at twilight so they must still like the mesh/house too. Bats sure do leave the house quickly. There is no stopping at the entrance to look around!