Measure the width of the existing decking with the tape measure and write this down for use later.
Remove the existing wood screws or carriage bolts. If the deck is old the screws may break off or strip out. Try a power screwdriver or a socket wrench.
Remove the existing wood decking. Where you encounter stripped screws or carriage bolts a pry bar may be required to remove the wood.
Cut off any stripped screws or carriage bolts. Use a 4-inch grinder with a cutoff wheel.
Remove any surface rust on the steel subframe with the 4-inch grinder and a grinding wheel.
Paint the metal subframe with an undercoating paint to protect it from rust. Let this dry before proceeding. Follow the directions on the undercoating paint for the correct application.
Measure the trailer from the front to the rear where the deck boards go. This will provide the dimension to cut the new decking boards to length. Cut the material with a miter saw.
Cut the deck boards to match the old ones from Step 1. A table saw works best for this.
Router the four sides of the deck board. Use a 1/4-inch roundover bit. This will keep the boards from splintering on the edges.
Secure the deck boards to the metal subframe using self-tapping metal screws. Use two screws at each subframe location. Place the screws 3/4 inch in from the side of the deck boards, to prevent splitting. An electric drill works best.
