We own a 140 year old log cabin near Algonquin Park ,in ontario. Our childredn are really stuffy after a couple of days visit. There is black mold on the inside roof boards of both bedrooms and on the roof boards of a screened in porch that runs along the front of the cabin. How can I get rid of the mold, and what should i treat the wood with to prevent mold? Also I have been cleaning the inside logs ( which have never been stained or treated) with Murphy’s woodsoap, would staining them make it