A building material adapted for controlling growth of vegetative fungi from spores having a compressed calcium sulfate layer, a paper layer over the sulfate layer, an adhesive for securing the paper layer to the sulfate layer; an amount of between about 30 wt % to 50 wt % of a salt of formic acid disposed on the paper layer thereby forming sheet rock with an ionic lattice on the surface to prevent vegetative growth from fungi spores, and a paint, an adhesive, a sealant, and an insulation each containing an antifungal amount of a salt of formic acid, such as potassium formate.