In response to the recent blog regarding the placement on birdhouses in backyard settings, one of our fellow bloggers requested information concerning the minimum size of entrance holes recommended for the species mentioned. Realizing many others might have the same question, below you will find this information. In addition, I have included the recommended minimum height a box should be placed above the ground for each of these eight species.
| Species | Minimum Hole Size | Height Above Ground |
| Eastern Bluebird | 1.5″ | 5′ |
| Carolina Chickadee | 1 1/8″ | 5′ |
| Tree Swallow | 1 3/8″ | 5′ |
| Tufted Titmouse | 1 1/8″ | 5′ |
| Carolina Wren | 1.5″ | 5′ |
| House Wren | 1 1/8″ | 5′ |
| Great Crested Flycatcher | 1.5″ | 6′ |
| Brown-headed Nuthatch | 1 | 5′ |
Should birdhouses be cleaned out each year? If so, what season/months is safe to clean them so that the next nesting season is not disturbed?