Repairing Decking or Joists

2-4 hours

Safely repair the wood for any deck or joist

Repairing Decking or Joists

Repairing a small area of your deck can save you time & money. If a cosmetic issue, remove the plank, flip and refasten. If repairing a damaged joist, support the deck on one side of the deck or it could crash, and match the wood replacement with similar type pressure-treated lumber. This guide will teach you to safely repair any deck or joist.


Removing nails & screws
Repairing Decking or Joists - Removing nails & screws

Remove nails or screws from the damaged decking board using a pry bar, screwdriver or drill. If the fasteners won't come out, chop the board into pieces with a chisel or saw, pry up the slivers, and replace.

Inspect Joists
Repairing Decking or Joists - Inspect Joists

Inspect the joists underneath for signs of rotted wood. Repair and reinforce joists that have soft, discolored areas with rotted wood putty.

Remove rotted portions
Repairing Decking or Joists - Remove rotted portions

Use a hammer and chisel to remove any rotted portions of joists.

Apply sealer
Repairing Decking or Joists - Apply sealer

Apply a thick coat of clear sealer to the damaged joist. Let it dry, and then apply a second coat of sealer. Cut a reinforcing joist from pressure-treated lumber.

Reinforce the joist
Repairing Decking or Joists - Reinforce the joist

Treat all sides of the reinforcing joist with a clear sealer and let it dry. Position the reinforcing joist tightly against the damaged joist, and attach it with 16d (3.5") galvanized nails driven every two feet or fasten it with 3 1/2-inch galvanized deck screws.

Cut replacement deck board
Repairing Decking or Joists - Cut replacement deck board

Attach the reinforcing joist to the ledger and header joist by toenailing with nails or screws. Cut replacement deck boards from matching lumber, using a circular saw.

Clean deck wood
Repairing Decking or Joists - Clean deck wood

If the existing decking is gray, "weather" the new decking with a solution made from 1 cup of baking soda and 1 gallon of warm water. Apply in the solution with a scrub brush. Rinse and let dry.

Apply wood stain
Repairing Decking or Joists - Apply wood stain

Use wood stain that is the same color as the rest of the deck and apply stain to both sides of the board and the edges.

Attach new decking
Repairing Decking or Joists - Attach new decking

Position the new decking and attach it to joists with galvanized deck screws or nails. Make sure the space between boards matches that of existing decking.