I am looking into redoing upstairs of 65 yearold home, there is a little bit of sawdust in the walls now bout not much. i am also having the wiring redone at the sametime. i live in ontario so we get some cold winds. i no i can get blowin but i dont really like it. my problem is i have two layers of drywall then laths and than a 1 inch board. does anyone no why there is a board there usually just laths on the studs. i hope someone can help.can i remove the inside board?