The Pivot-Pole Bat House Mounting System
Brian Keeley and Mark Kiser
Mounting bat houses on poles at the recommended height (12 feet or higher)
can be a difficult task. Because many bat house enthusiasts have requested
easier methods to mount their bat houses on poles, we have designed a fairly
simple technique called the "pivot pole," which has the added advantage of
allowing the bat house to be raised or lowered for maintenance. Similar
techniques have been developed for purple martin houses.
For simplicity, our illustration in Figure 2 shows only one bat house. However,
this method can be used to mount back-to-back pairs as well. When installing
two bat houses back-to-back, we recommend using two poles and larger
diameter bolts for added strength. As always, a 3/4- to 1-inch space should
be left between back-to-back mounted houses to create additional roosting
space and venting on hot days (consult The Bat House Builders' Handbook
for more details).
Here are the steps to construct a pivot-pole mounting system for your bat
house:
1. Select a suitable pole. Good choices are wooden 4x4-inch posts (available
in 10-, 12-, and 16-foot lengths) or steel poles (usually available in 10-foot
lengths; use a 1 1/2- or 2-inch diameter pole). If you use a steel pole, spacers
positioned between the 2x4 braces and pole are necessary (see Figure 3).
Washers, blocks of wood, pieces of PVC pipe, electrical conduit, etc., can
serve as spacers.
2. Select a suitable location (consult The Bat House Builders' Handbook for
assistance). Dig a hole 3 feet deep and roughly 8 to 10 inches across. Line
the bottom of the hole with several inches of gravel (this will help prevent
wooden support posts from rotting).
3. Cut a 6-foot piece from a treated, 4x4-inch post. Next, cut an 8-foot length
of 2x4 lumber into two, 4-foot pieces. The 4x4 post and 2x4 braces combined
serve as the support post, which later will be anchored in the ground with
concrete.
4. For drilling holes through the support post components and the pole, make
a template by cutting out a 3 1/2- by 24-inch piece of cardboard. Draw a 1/2inch hole (centered) six inches from each end, then cut out the holes in the
template. Place the template on one side of the 4x4 post, and align the top
edge of the template with the top of the post. Using the template, mark and
drill two, 1/2-inch holes through the post (Figure 3).
5. Position the template at the top of one of the 2x4 pieces, aligning the top
edge of the template with the top edge of the 2x4. Mark the 1/2-inch holes,
then move the template to the bottom edge of the 2x4. Align the bottom
edges, and mark the holes. To ensure accurate drilling, stack both 2x4s
together, and drill all four holes through each 2x4 at the same time.
6. Place the template on the pole, and align the bottom edge of the template
with the bottom edge of the pole. Next, slide the template down such that
11/2 inches of the template extend beyond the bottom edge of the pole. This
will ensure that the pole does not strike the support post when raised. Mark
the holes on the pole, and drill two 1/2-inch holes through the pole. If you
have selected a steel pole, you will need a drill bit specifically designed for
metal, and you will need to lubricate the drill bit with oil while you drill. Set the
pole aside for now.
7. Using two 8 x 3/8-inch, galvanized, hex or carriage bolts (Bolts C and D),
and two 3/8-inch hex nuts and washers, attach both 2x4 braces to the 4x4
post as shown in Figure 3. Tighten the hex nuts firmly. Attach a metal bar or
bracket (optional, but recommended) to the 2x4 braces, four inches from the
top of the 4x4 post, using 1 1/2-inch lag screws or wood screws as shown in
Figure 3. This will serve as a "safety stop" to prevent the pole from falling
over while the bat house is being raised. The support post is now complete.
8. Set the support post into the ground, ensuring that the bat house will face
the desired direction. A compass may be helpful. Using a level, straighten the
post so that it is vertical. You may wish to line the hole with rocks to help
straighten the post, and to aid in setting the concrete. Mix and pour concrete
into the hole and allow it to set.
9. Attach your bat house securely to the other end of the pole. For details,
see The Bat House Builders' Handbook.
10. Place the lower end of the pole on top of the 4x4 post. Lift the end of the
pole until Hole A on each 2x4 brace lines up with Hole A on the pole. Insert
an 8 x 3/8-inch bolt (Bolt A), and 3/8-inch washers, through Hole A (and
spacers if necessary) in each 2x4 and pole (Figure 3). Place a 3/8-inch hex
nut on the bolt and tighten, but do not tighten completely. The pole should be
just loose enough to be raised.
11. To raise the bat house and pole, you may need the assistance of another
person. Slowly stand the pole up until it is vertical (Hole B on each 2x4
should now be aligned with Hole B on the pole). The safety bracket should
prevent the pole from falling over the other way. Insert the other 8 x 3/8-inch
bolt (Bolt B), with washer (and spacers if necessary), through Hole B in each
2x4 and pole, and place the remaining 3/8-inch washer and hex nut on Bolt B
(see Figures 2 and 3). Tighten both hex nuts firmly. Your bat house should
now be ready for use.
12. If you need to lower your bat house for cleaning, repainting, or other
maintenance, remove Bolt B, and, with assistance, slowly lower the bat
house to the ground.
Larry Keeley of College Station, Texas, demonstrates the operation of the
pivot pole. To lower the house, he simply removes the lower bolt.
PHOTO BY BRIAN KEELEY
PIVOT-POLE BAT HOUSE
Recommended Tools
• saw
• post-hole diggers and shovel
• drill
• 1/2-inch drill bit, >3 1/2-inches-long (metal cutting type and lubricating oil if
pole is steel)
• adjustable wrench or 3/8-inch socket/socket wrench
• tape measure or yardstick
• pencil
• compass
• knife
• level
Materials List
• 6-foot length of treated 4x4-inch post
• 8-foot length of 2x4-inch lumber
• pole (10 foot or longer 4x4-inch post, or 1 1/2- or 2-inch diameter steel pole)
• 4 each, 8 x 3/8-inch hex or carriage bolts and nuts
• 8 washers, 3/8 inch
• metal bracket or bar (optional, but recommended)
• 1 1/2-inch lag screws or wood screws for metal bracket
• * 1/2-inch diameter spacers (for steel poles only)
• 3 1/2 x 24-inch piece of cardboard
• gravel
• concrete mix and mixing supplies
COURTESY OF BRIAN KEELEY, BCI
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