Abstract: A modularly stackable centrally ventilated bird house that includes a main portion, a ventilation system, and a base. The main portion includes a lowermost floor, corner posts, lower peripheral perches, a pair of lower internal perches, an uppermost floor, upper peripheral perches, a pair of upper internal perches, and a ceiling. The ventilation system includes a stub venting-tube that together with a throughbore in the lower floor allow the modularly stackable centrally ventilated bird houses to be stacked, four lower compartments, four lower dowels, four upper compartments, four upper dowels, and a vent cap. The main portion further includes a pitched roof that is selectively disposed on the ceiling and which has a pair of gable ends that have vent throughbores therethrough. When the pitched roof is utilized, the vent cap is removed and air exiting the stub venting-tube exits through the vent throughbores in the pair of gable ends of the pitched roof and out into the ambient.