Single-chamber Bat House (wall mounted)
Materials (makes one house) 14 sheet (2' x 4') 12" AC, BC or T1-11 (outdoor grade) plywood
1. Measure and cut plywood into three pieces:
One piece 1
" ( 3 4 "
x 112" finished) x 8' pine (furring strip)
5" x 24"
20 to 30 exterior-grade screws, 1" One pint dark, water-based stain, exterior grade One pint water-based primer, exterior grade One quart flat, water-based paint or stain, exterior grade One tube paintable latex caulk
1" x 4" x 28" board for roof (optional, but highly recommended)
Black asphalt shingles or galva n i zed metal (optional) 6 to10 roo ing nails, 78" (if using shingles or metal roofing)
Recommended tools Table saw or handsaw Variable-speed re versing drill Screwdriver bit for drill Tape measure or yardstick
Caulking gun Paintbrushes Hammer (optional) Tin snips (optional)
Roughen inside of backboard and landing area by cutting horizontal grooves with sharp object or saw. Space grooves 14" to 12" apart, cutting 132" to 116" deep.
Apply two coats of dark, water-based stain to interior surfaces. Do not use paint, as it will ill grooves.
Cut furring strip into one 24" and two 2012" pieces.
Attach furring strips to back, caulking first. Start with 24" piece at top. Roost chamber spacing is 34".
Attach front to furring strips, top piece irst (caulk first). Leave 12" vent space between top and bottom front pieces.
Caulk all outside joints to further seal roost chamber.
Attach a 1" x 4" x 28" board to the top as a roof (optional, but highly recommended).
Apply three coats of paint or stain to the exterior (use primer for first coat).
Cover roof with shingles or galvanized metal (optional).
Mount on building (south or east sides usually best).
Optional modifications to the single-chamber bat house
1. Wider bat houses can be built for larger colonies. Be sure to
adjust dimensions for back and front pieces and ceiling strip.
1 / 2 " vent
A 3 4 " s u p p o r t s p a c e r m a y b e n e e d e d i n t h e c e n t e r o f t h e r o o s t - ing chamber for bat houses over 24" wide to pre vent warping.
2. To make a taller version for additional temperature diversit ,
use these modifications: From a 2' x 8' piece of plywood, cut three pieces: 51" x 24", 33" x 24" and 12" x 24". Cut two 8' furring strips into one 24" and two 44" pieces. Follow assem- bly procedure above.
3. Two bat houses can be placed back-to-back, mounted between two poles, to create a three-chamber nursery house. Before bl h l 3 " l h b k f h h assem , cut a orizonta 4 s ot in t e ac o eac ouse about 9" from the bottom edge of the back piece to permit movement of bats between houses. Two pieces of wood, 1" x 4" x 414", screwed horizontally to each side, will join the two b 3"b hh dh oxes. Leave a 4 space etween t e two ouses, an roug en the wood surfaces or cover the back of each with plastic mesh (see item 5 below). Do not cover the rear exit slots with mesh. One 1" x 4" x 34" ve rtical piece, attached to each side over the horizontal pieces, blocks light but allows bats and air to enter. A galvanized metal roof, covering both houses, protects the center roosting area from rain. Eaves should be about 3" in southern areas and about 112" in the north. 4. Ventilation may not be necessary in cold climates. In this case, the front should be a single piece 23" long. Smaller bat houses like this one will be less successful in cool climates. However, those mounted on buildings maintain thermal stability better and are more likely to attract bats. 5. Durable plastic mesh can be substituted to provide footholds
More bat-house plans and additional information can be found in BCI’s Bat House Builder’s Handbook, available at www.batcatalog.com.
for bats. Attach one 20" x 2412" piece to backboard after stain- ing interior, but prior to assembly.
© copyright Bat Conservation International, Inc. All rights reserved.