Holy Year of the Bat, Batman!

Rewind back to 1922 when the first vampire film was released-bats are frequently portrayed as dirty, scary varmints you don’t want to come into contact with.  But in real life, you will find bats are very clean, not-that-scary animals, acting as natural pest controllers and eating up to 1,000 mosquitoes in a single hour!

Surprised? Bats aren’t confined to caves, spending the majority of the summer living in trees, under bridges, or in old houses. You may already have them in your area, so why not take advantage of their insect eating powers by building a bat house.  When built correctly, bat houses mimic an ideal bat environment-tight, dark, and warm. Follow the steps below to build your own bat house.

Constructing a Bat House

Tools ·  Measuring tape ·  Straightedge ·  Combination square ·  Spring clamps ·  Safety glasses ·  Jigsaw ·  French curve and circle templates ·  Drill fitted with .25” drill bit ·  Caulking gun ·  Paintbrush ·  Foam roller ·  Scissors ·  Staple gun

Supplies ·  2’x 4’ section of ½” exterior grade plywood ·  One 6’ 1x2 ·  ½” deer netting ·  Exterior latex paint – black and another dark color ·  Low VOC adhesive caulk ·  1” deck screws ·  3 ½” deck screws ·  3/8” Staples

Directions

1. Measure and cut the plywood
Using a tape measure and straightedge, mark up for cutting a 2’x4’ piece of ½” exterior-grade plywood. You’ll need one piece that’s 2’ wide x 26” long and one that’s 2’ wide x 22” long. Clamp the plywood to a worktable. Make sure you have on safety glasses, then use a jigsaw or a circular saw to cut the plywood.

2. Draw the bat design
Create a bat cut out using circular and oblong templates called French curves (available at most office supply stores). Lay out the bat shape on the edge of the shorter piece of plywood, making sure it’s 24” wide. 

3. Drill holes for the jigsaw
Clamp the plywood and bat design to your worktable, making sure the whole bat hangs over the edge. Using a drill/driver with a ¼” bit, drill holes just inside the points of the bat shape. This will make it easy to turn your jigsaw blade as you cut out the curved parts.

4. Cut out the bat
Using a jigsaw fitted with a narrow scroll blade, which is designed for making intricate curves, cut out the bat design. Cut the shape closest to the edge first, then cut the whole bat from the sheet. Because both halves of the cutline need to look clean, work slowly and carefully. Whenever you get to a drill hole at one of the points, stop the saw and turn it before you continue.

5. Make the sides
To raise the front panel off the back and create a small crawl space to house the bats, you’ll need strips of lumber around the edges. Cut three pieces from a 1x2-one 24” piece and two 19” pieces.

6. Attach the sides
Using a caulk gun, lay a bead of caulk along the face of the long 1x2. Line it up with the top edge of the larger piece of plywood and clamp it in place with spring clamps. Using a drill/driver, drive 1” deck screws through the 1x2 and into the plywood every 6 inches to hold it in place.

Attach the two shorter pieces to the sides in the same manner and caulk the ends where they meet the top piece before you clamp them down. Use a damp rag to wipe up any caulk that oozes out.

7. Paint the parts
Using a brush and roller, paint the back piece black, from the top edge to the ends of the 1x2s. Also paint the back of the front piece black. These will form the dark inside of the bat house.

Paint the other surfaces in a color that will help maintain a healthy temperature inside the house. If you live in the North, a dark color can keep the house toasty by absorbing the sunlight. In the warm South, a light color may be a better choice. Be sure all surfaces of the wood are painted and well sealed.

Let the paint dry completely.

8. Attach the netting
Unroll the deer netting and lay it over the inside of the back section, flat against the plywood. Using a staple gun, attach the netting to the inner edge of the top 1x2 and along the sides. Make sure to pull it taut so it can’t sag when bats hang from it. Extend the netting all the way over the bottom edge and wrap it around to the back. Once it’s stapled all around, cut off the excess.

9. Attach the front piece
Caulk along the face of the 1x2s on the back section. Place the front piece onto the 1x2s with the bat shape facing the bottom, and the top edges and corners lined up. Clamp it in place. Drive 1” screws every 6 inches through the face and into the 1x2s to secure it.

10. Put on the bat cutout
Caulk the exposed sections of the 1x2s, then place the cutout onto them just below the large front piece. Leave a ½” gap between the two for the air vent. Clamp the piece and attach it in place with a single 1” screw on each side.

11. Hang it up
Hang your bat house under the eaves of your house or from a tall, flat pole made from pressure-treated lumber (make sure to bury one-third of the lumber in the ground to keep it steady). Attach it by driving 3½” deck screws through the corners into the siding or fascia of your house, or if you’re using a pole, along the middle at the top and bottom.

The bat house should be at least 15 feet off the ground, away from bright lights. Choose a place facing south so it gets plenty of sunlight (aim for 6 to 10 hours of exposure). This will keep it nice and hot—just the way bats like it!

These directions and more building tips can be found at: http://www.thisoldhouse.com/toh/how-to/intro/0,,20165965,00.html