... But they're certainly welcomed in this house!

There are a number of bat house plans on the Internet. * Here is one of Scott Holub's plans. To see other plans visit Scott's Bat House Page and Bat House Plans: http://habitat.ms11.net/ bat/bathome.htm.

This two-chamber bat house is made from one sheet of plywood and two 2x4x8s. Choose this plan if you want multiple bat houses, but don't want to spend too much. It's perfect for lower cost experimentation. Try venting one and not the other or painting them different colors. Improvements in this plan over the original "medium bat house" include taller chambers, much simpler plywood cuts, and slightly easier assembly. Chamber dimensions: 14" wide x 30.5" tall

Experiments are still needed to see which factors affect bat house success. For experiments to be most helpful build several bat houses and keep all factors, except one, the same to test the effect of that single factor.

Materials List

   2--2"x4"x8" untreated cedar, fir, or
pine
   1 sheet 3/8" plywood (ACX, BCX, or
T1-11 grade)
   1 lb. box of screws--2 1/2" exterior
grade
   1/2" spade bit
   1 lb. box of 6d nails--outdoor
   1 tube caulk--exterior paintable
   1 sheet of sandpaper medium-course
grit
   1 quart exterior latex primer
   1 quart exterior latex paint (see color
info)
   1 can black spray paint
   plastic mesh (optional)
   1/4" exterior staples (optional)
   Plus any material for installing
house (will vary).

Tools required:

     Table saw or circular saw
     Tape measure
     Power drill with bit for screws and
1/2" spade bit
     Caulking gun
     T-square or straight edge
     Paint brush (4")
     Hammer
     Safety goggles
     Ear protection
     Staple gun (optional)
     Dado blade (optional, but helpful)

You can get two houses from a single
sheet of 3/8" ACX, BCX, or T1-11 exterior
plywood (CDX is ok) and 2 untreated 8
2x4's (1.5" x 3.5" x 8').

Instructions:

1) Cut out the pieces from the
plywood (use ACX, BCX or T1-11
for better longevity then CDX). The
measurements with "~" should be the
last cuts. Note that slats 1.B part I and
1.B part 2 should be stacked together
to make one complete slat similar to
the others. The bats won't care that
it is more then one piece and no one
can see it.

2) You have two options for the
sides and ceilings: a) If you have a
table saw, rip the 2x4's to 3" wide
(preferred), b) If not just continue.

3) Groove the worst looking side
of the 2x4 the long way with 3/4"
spaces (15/16" spaces if you didn't
rip the boards to 3") and 3/8" wide
by 1/2" deep grooves to fit the slats
(a total of 2 grooves each house). See
the picture to the right below. A table
saw with dado blade is very helpful,
but you can do it with a router or a
skill saw and a chisel. You will also
need to dado out a place in the sides
for the ceiling to fit (1-1/2" wide,
across the short way, just below the
angle for the roof.)

4) Check to see that the plywood
actually fits in to the groove without
too much trouble, if it doesn't then
make the groove a little wider. This
will save you a lot of time later. It
should be snug, but not so snug that
you can't get it in.

5) Make the crosscuts on the
2x4's.

6) You should lightly groove or
scratch (1/32" to 1/16" deep) the
plywood slats on both sides as well
as the insides of the back and the front
at about 1/2" horizontal intervals so
the bats can hang on better. Use a
skill saw or a utility knife. Groove
the landing pad too (the lowest 6" of
the inside of the back). Alternately
you can staple on 1/4" or 1/8" plastic
mesh instead of grooving it, but make
sure your staples don't go through
the plywood.

7) Slide the ceiling into the wide
grooves in the side so the narrow
grooves in the ceiling all line up with
the narrow grooves on the sides.
Screw the ceiling to the sides.

8) Screw the back to the sides and
ceiling with 4 to 6-2-1/2" exterior
grade screws making sure you don't
block the grooves with the screws.
(Note: the plywood won't be flush
with the outer edge of the sides.)

9) Caulk the joints between the
back and the sides (Exterior latex or
silicone paintable caulk). Caulking is
very important to retain heat.

10) Slide in the slats and tack them
in with I or 2 nails each (they should
fit pretty snugly so you might have to
tap them in with a hammer.)

11) Put a bead of caulk along the
top diagonal face of the sides.

12) Screw on the roof.

13) Put a bead of caulk along the
front face of the sides.

14) Screw on the front (make sure
it is snug with the roof).

15) See the note (below) about
venting-now is a good time to put
the vents in if you are going to.

16) If the slat boards warp a lot you
might want to put 3/4" spacers in each
crevice and screw them in place with
long screws from the front and back.
(Hint: stack 2 small scrap pieces of the
3/8" plywood for a spacer.)

17) Caulk around the outside of
the roof, front, and back joints.

18) Allow all caulk to dry

19) Sand, prime, and paint the
whole outside with at least two coats
of black or appropriate color paint. (I
used brown in southern Oklahoma,
because summers get pretty warm
here.)

20) Paint the bottom of the slats
and up into the chambers a little way
with black spray paint. A light coat
will do. The bats like the dark.

* If you don't have Internet access, Scott will send you a printed version of his plans for $6.99. Just send a SASE (with two stamps) requesting 'printed bat house plans' to: Scott Holub, 14734 County Road 3583, Ada, OK 74820. (No in-person visits please.)

Scott Holub

ADA, OKLAHOMA