The drawings in this book have been made as nearly correct as careful study of all available data on the subject will allow. The author feels confident that if the drawings, together with the specifications that go with them, are carefully followed the artisan will be amply rewarded by finding all bird tenements “let” as soon as the spring migration and nesting season starts.
These houses and many of varied design have been successfully built by pupils of the seventh and eighth grades, with over 75 percent of success in having them occupied.
The table given below gives the correct dimensions for a variety of houses for different birds.
The size of the opening is very important, as it is essential that it be no larger than is necessary for the bird for whom it is intended, to conveniently enter.
The smaller birds will be bothered a great deal by the English sparrow, who enters if the opening is not kept very small.
It is considered by a majority of authorities that a perch is not a help but a hindrance at the opening. The sparrows alight there and by their incessant chirping drive out or annoy the more desirable occupants. Again, the bluebird and most of the other song birds can fly directly to the edge of the opening and thus go in, while the sparrow, not quite as clever, must first alight on the perch and get his bearing before hopping in.
It is exceedingly important that there be some means of cleaning out Bird Houses at the season’s end or to remove any dead birdlings during the season. This may be taken care of by having either the roof or the bottom hinged.
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 |