Why is tarm paper or plastic sheeting put under hardwood floors?
They are basically used as a vapor barrier to reduce the expansion/contraction of the floor. Tar paper will also cushion and quiet the floor just a little bit.
1. Vapor barrier. 2. Cushion. 3.To allow the floor to move as it expands and contracts on drying/absorbing moisture. (You leave a gap at the edge don't you?)
