Fix a Bouncy Deck
Q: Our rear deck is a little too bouncy. Is there any way to stabilize this without a complete rebuild?
A: A “bouncy” deck is usually caused by long joists between beams. Assuming you can access the support framing, you can strengthen the deck by installing rows of blocking cut to fit tightly between the joists, spaced every 3 to 4 feet along the span. The blocking should be the same size as the joists (usually made of 2-by-8 or 2-by-10). Drive three 16d galvanized nails through the joists into each end of the blocking. The blocks should be installed in a staggered pattern.
Another option to stabilize the deck: Install an additional beam and support posts to the deck framing. But the blocking method is less complicated.