Has anyone made these? Seem the dimensions run from 2" diameter to 3-1/2" diameter. Length 4-5" and hole 3/4" above center with a perch seem constant. Do you need to make the top removable? What's the best finish for outdoors?
I have made a number of Bluebird size turned bird houses
They have been used by Bluebirds, nut hatches, chickadees, flying squirrels...
I put no finish inside but do put a couple coats of spar varnish on the outside. No perch needed.
Perches are used by predators and birds don’t need them.
Is this an ornamental house? I am pretty sure Hummingbirds don’t use boxes of any type but it could be something new to learn.
Hummingbirds do not nest in houses/cavities. Probably started as a cute marketing name that somebody came up with for small ornamental houses. Wouldn't be surprised if some are selling them by saying they will attract hummingbirds.