I am building my coop from lumber that came out of a nearby house. As I've made my way through the pile, there is evidence of previously wetted sheetrock (small discolored pieces still attached) and some powdery 'stuff' on many of the studs. I suspect it's mold. Some is white and some is yellow in color. Overall, I suspect that either this could have occurred while the wood was piled in the yard, or the walls and studs were removed due to flooding. As construction material is this a potential problem for my girls? I am in the framing stage and ready to work on the roof. Before I wall up the hen house and attach the hardware cloth, should I do anything to the wood? Should I scrub, or power wash, or seal, or.........................the wood?