Abstract: A multi-sided building construction assembly having a plurality of side wall units, a like plurality of generally triangularly configured roof panels, a like plurality of combination union brackets, and a like plurality of footing brackets, with a roof center hub support having a like number of sides. The combination union bracket is configured for being received and connected atop the adjacent edges of adjacent side wall units, and include a pair of upwardly and angularly disposed roof connecting brackets. The roof center hub support has a number of side edges, each of which is disposed at the angle necessary for the pitch of the roof panel, which is supported at one end by the brackets of the union bracket member, and at the other end by the roof center hub support. The footing brackets include angularly disposed arms at the appropriate angle for the polygon, and attach beneath adjacent edges of adjacent side wall units and may be attached to a concrete slab.