Abstract: A combination roof structure and solar collector for a building having vertical side walls and end walls. A plurality of laterally spaced trusses or bar joists extend from one wall to an opposite wall. A translucent panel is carried on top of the upper members which form part of the truss providing a roof surface for the building while permitting solar energy to pass therethrough. Panels are attached to elongated lower members forming part of the truss so as to define a chamber between the upper members of the truss and the panels. A solar energy absorbing surface is carried above the panels attached to the lower members. Insulation is provided between the solar energy absorbing surface and the interior of the building for insulating the interior of the building from the chamber. Air is circulated through the chamber for absorbing heat from the solar energy absorbing surface and the heated air is supplied to the interior of the building or to a rock storage.