COMMON DECK PROBLEMS
Loose deck boards - Wood expands when it gets wet and it shrinks when it dries. As the wood moves, the deck gets more elastic and bouncy and nails and screws that were once tight, get loose. To fix this problem, add coarse-threaded, galvanized deck screws alongside nails to cinch down loose deck boards. Use a nail punch to drive existing nails farther into the joists. Be sure to stand or kneel on the deck boards as you screw them, so they're tight.
Swaying posts and beams - As beams and posts lose their stiffness, they become more elastic and "bouncy". A quick fix for this problem is to install cross braces between posts and beams to take out the sway. Cut 4 x 4s or 6 x 6s (the longer the better) with 45-degree angles on each end. Use 6-inch or longer lag bolts to secure the ends to the posts and beams.
Loose guardrail posts and pickets - Install lag bolts and washers to firm up guardrail posts and pickets by pre-drilling holes, then installing one or more lag bolts. This will hold pickets and posts firmly to the deck rim.
Bouncy deck surface - Add blocking between joists to reduce bounce. This will unify the joists so that weight applied to one joist is partly distributed to those on either side. Don't install blocking directly under gaps between the deck boards though, as this will create areas that hold water.
Loose or wimpy stairs - Temporarily remove the stairs and add solid stringers to the two outside stringers. If necessary, add 2 x 4s to both sides of the middle string to increase strength.
Ineffective joist hangers - Joists may shrink so that their bottoms no longer rest on existing hangers. The easiest fix for this problem is to install wedges and drive them into the gap until they're snug. Some decks are even constructed without joist hangers. If this is the case, install them using 16d galvanized nails to secure them to the ledger strips and beams. Use galvanized stubby nails for the joists.
Discolored wood - A wood conditioner can be applied, followed by pressure washing, to remove any old coatings. Prepare the surface for refinishing by letting the deck dry, then sanding and repairing any flaws. Use an oil base, naturally pigmented, penetrating finish for a natural wood look that will protect the deck from rain and sun, yet still will still show the grain of the wood.