NEW –TheCornellLab of Ornithology offers the following on building a proper Nest Box.
NEW –The North American Bluebird Society (NABS) Nest Box Recommendation.
Gilbertson Nest Box Mounting System
Steve Gilbertson has developed a very simple, effective, and inexpensive mounting system that works for most light to medium weight nest boxes. The main components of the system are a 5 foot long section of ½” electrical conduit and a 48” long piece of ½” diameter reinforcing bar (or rebar for short). These can easily be purchased at most home centers for a few dollars. The other hardware needed is a ½” EMT coupling with one ¾” screw to replace the shorter one at the bottom and possibly one or two ½” conduit straps to secure the top of the hole to the house.
Once a suitable location is found for the box, the 48” rebar is pounded into the ground with a mallet to about an 18” or 24” depth. Then, the 5’ conduit is slid over the top of the rebar exposed above the ground with the ½” coupling on the bottom near the ground. The screws in the coupling are then tightened to the conduit and rebar to prevent turning relative to each other. Finally, the nest box can be mounted to the top of the pole using whatever method is suitable for the particular nest box design. Download a diagram showing the Gilbertson Mounting system here Nest box pole assembly and installation instructions- Download PDF.
Gilwood Slot Box
Design by Steve Gilbertson. This is one of the very simplest bluebird nest box designs you can build. There is no entrance hole to drill due to the open top slot entrance. The open entrance and shallow design make it less attractive to House Sparrows. Also, this slot entrance is safer for bluebirds as it allows them to more easily escape from the box if a sparrow enters it while the bluebird is inside. The box also incorporates a double thickness roof which helps provide better heat retention and insulation from summer sun. When building the box, it is important to make sure that the slot entrance is at least 1 3/16” high. So, install the door as one of the last steps and trim it down if necessary. Also, the material list calls for using all 1” by 8” cedar. But, if you don’t have a table saw, it is probably easier to use some 1 x 4 stock instead. Click here for Gilwood Slot Box Plans – Download PDF
Developed in Minnesota by Dick Peterson, and features a large, angled roof, angled sides, a small sloping floor, and a vertical, oblong hole instead of the traditional round one. The advantages of this design are a) the slanted floor keeps the nest drier, b) the large, angled roof makes it harder for predators to reach the nest, c) ease of nest checks via the front panel which swings down. However, it can be a complicated design to build requiring better than average tools and woodworking skills and as the box is heavier than most other designs it can be trickier to mount. But, starlings don’t prefer it as a nesting site and will usually go elsewhere.Click here for Peterson Nest Box Plans – Download PDF.
Xbox Bluebird Nest Box
This is a great, simple nesting box design developed by Tom Comfort of Antrim County and a committee of national bluebird house experts including Minnesota’s Steve Gilbertson and Keith Radel. Early testing results show the bluebirds really prefer it over many other designs. It features a 1 9/16″ hole, slightly larger than the traditional 1 1/2″ hole size. It is designed to be mounted using 1/2″ electrical conduit and rebar. See details above. It is easy to build and can be constructed with either cedar or pine. However, cedar will be more expensive and it may be hard to find wide enough lumber for the roof at your local building store. Click here for Xbox Nest Box Plans – Download PDF.
Gilbertson PVC Box
This nest box is made from white 4-inch diameter PVC sewer and drain (S&D) pipe. The walls are barely more than 1/16 inch thick and will be slightly less heat resistant than the heavier walls of Schedule 40 PVC pipe. Steve Gilbertson uses the thinner-walled PVC because it is more flexible, and flexibility is what makes his unique box-opening method work. Click here to download the plans for the approved BBRP modified version of the Gilbertson PVC Nest Box – Download PDF.