Typical Bird House Specifications.
| Bird | Floor Area in Inches | Depth in Inches | Entrance Above Floor in Inches | Diameter of Entrance in Inches | Height From Ground in Inches |
| Bluebird | 5×5 | 8 | 6 | 1½ | 5-10 |
| Robin | 6×8 | 8 | [A] | [A] | 6-15 |
| Chickadee | 4×4 | 8-10 | 8 | 1⅛ | 6-15 |
| Tufted Titmouse | 4×4 | 8-10 | 8 | 1¼ | 6-15 |
| White-breasted Nuthatch | 4×4 | 8-10 | 8 | 1¼ | 12-20 |
| House Wren | 4×4 | 6-8 | 1-6 | ⅞ | 6-10 |
| Bewick Wren | 4×4 | 6-8 | 1-6 | 1⅛ | 6-10 |
| Carolina Wren | 4×4 | 6-8 | 1-6 | 1⅛ | 6-10 |
| Dipper | 6×6 | 6 | 1 | 3 | 1-3 |
| Violent-Green Swallow | 5×5 | 6 | 1-6 | 1½ | 10-15 |
| Tree Swallow | 5×5 | 6 | 1-6 | 1½ | 10-15 |
| Barn Swallow | 6×6 | 6 | [A] | [A] | 8-12 |
| Martin | 6×6 | 6 | 1 | 2½ | 16-20 |
| Swallow | 6×6 | 6 | 1 | 2½ | 16-20 |
| Song Sparrow | 6×6 | 6 | [B] | 1-3 | |
| Crested Flycatcher | 6×6 | 8-10 | 8 | 2 | 8-20 |
| Red-headed Woodpecker | 6×6 | 12-15 | 12 | 2 | 12-20 |
| Golden-Fronted Woodpecker | 6×6 | 12-15 | 12 | 1½ | 12-20 |
| Hairy Woodpecker | 6×6 | 12-15 | 12 | 1½ | 12-20 |
| Downy Woodpecker | 4×4 | 8-10 | 8 | 1¼ | 6-20 |
| Screech Owl | 8×8 | 12-15 | 12 | 3 | 10-30 |
| Sparrow Hawk | 8×8 | 12-15 | 12 | 3 | 10-30 |
| Saw-Whet Owl | 6×6 | 10-12 | 10 | 2½ | 12-20 |
| Barn Owl | 10×18 | 15-18 | 4 | 6 | 12-18 |
| Wood Duck | 10×18 | 10-15 | 3 | 6 | 4-20 |
There should be a few small holes bored in the bottom to allow any moisture that might accumulate, to drain. Also, another set of holes at least ¼-inch in diameter should be bored for ventilation, high enough so that no drafts will affect the young. These are best located just under the eaves.
In boring the entrance hole, tip the bit upward slightly so that rain water will not drip inward.
Some device for attaching the house to a building or tree should be provided. It is best to have the house stationary to prevent undue swinging in a high wind, perhaps causing the breaking of eggs and discomfort to the mother bird.
Houses of unusual shape or design are not considered as good as the plainer types, the idea being to make each house harmonize as naturally as possible with the surroundings.
It must be evident from the foregoing that there are quite a number of things to keep in mind as we prepare our plans for the homes of the future feathered inhabitants.