Abstract: A variable-volume birdhouse comprises an internal nesting volume that varies in height, width and breadth to suit desired bird species. The nesting volume maintains a generally cubicle interior shape. A plurality of generally orthogonal, intersecting plywood panels form the enclosure. The base panel supports a pair of spaced-apart, side panels that removably mount an upper roof panel. A perpendicular back panel extends between the side panels in spaced relation relative to a front door panel that is hinged to the enclosure for easy user access. Hooks projecting from the panels are received within suitable slits in adjacent panels to lock them together. An internal, vertical partition is slidably fitted within selected grooves in the base and rear panels to establish internal width. An appropriately-sized shelf is fitted between the partition and the right side panel. The nesting volume rear is bounded by an appropriately dimensioned rear wall.