A smart roof system and method comprising cementitious sheathing sheets for a roof cover that can be installed directly onto the wood roof sheathing of a structure or home. Said cementitious sheathing sheets are laid over wood roof sheathing directly with permanent adhesive. An aluminum expansion joint is installed to serve as an expansion joint between said cementitious sheathing sheets and to provide support for solar panels.
Aluminum expansion joints have a lower lip and an upper lip, a lower lip of the aluminum expansion joints serves to support cementitious sheathing sheets over the lower lip with adhesive and create a joint directly over the wood roof sheathing. The cementitious sheathing sheets are laid on the wood roof sheathing with an adhesive designed to adhere in a permanent manner to the cementitious sheathing sheets. A next cementitious sheet is then installed into the lower lip of the aluminum expansion joints and overlap on top of the previous cementitious sheet, bonding by the permanent adhesive. The procedure is repeated forming the roof from lower elevation to higher roof elevation, thereby water will flow over the overlapping sections of cementitious sheathing sheets.