- Q.What kind of adhesive should
I use to bond CCA-treated decking to treated
joists?
A.Preferably none. The
U.S. Forest Products Laboratory does not recommend
any adhesive between the decking and the joists.
The swelling and shrinking of the two members at
right angles to each other will break the bond of
any rigid adhesive. Many of the more flexible
mastic-type products on the market will stick to
treated wood, but the differential movement will
cause failure in a few years. Neither type of
adhesive is strong enough to prevent deck board
cupping.