Bat House Plans (4-Chamber)
A nursery house for colonies of bats
This four-chamber bat house is sized for a maternity colony. It stands 31" tall and 20" wide, with an attic under the roof and three baffles that divide the roost into four chambers. More chambers hold heat better than one, which is what a nursery colony needs.
The design
- Four roosting chambers, for better temperature control.
- Grooved inside surfaces, so bats can grip and climb.
- ½" ventilation holes in the sides to keep it from overheating in warm weather.
- An open bottom, so droppings fall free and the inside stays clean.
- A sloped roof with an overhang and a drip kerf to shed rain, over a sub-roof that keeps the inside dry.
- Holes in the baffles, so bats can move between chambers.
I build the boxes to check the plans, and refine the instructions from what I learn. More about how the plans are made.
A page from the plan: the Sides
What's in the plan
- A page for each part, with its dimensions, hole placements and construction steps: the sides, back, baffles, battens, roof, sub-roof, attic floor, upper and lower fronts, and back mounting board.
- Step-by-step assembly.
- How to finish it for your climate: dark in cold regions, medium brown in temperate ones, light in hot ones.
- Where and how to mount it.
- A sourced materials list, a cut diagram and an exploded view.
Materials
Exterior-grade ¾" plywood and cedar, with ½" plywood for the baffles. Stainless or brass screws, caulk, and an exterior stain or paint, plus a dark water-based dye for the inside. The materials list in the plan names each one.
Where it goes
Mount it on the outside wall of a building, such as a barn, garage, shed or house, not on a tree or a pole. Put it at least 12 feet up, 15 to 20 feet if you can, on a wall facing south or southeast for the morning and midday sun.
Not ready yet? See a complete plan first: the Carolina Wren plan is free.