Repairing a damaged floor in a boat begins with evaluating the extent of the damages. This allows you to generate a list of materials and assemble the tools needed to make the repairs. Some repairs can often be done without removing the seats or other accessories. Other repairs require removing fixtures or carpets that prevent access to the damaged floor in a boat. The methods used to make minor repairs to wood and fiberglass floors in a boat are similar in many ways. Major repairs or repairs to aluminum boat floors should be assigned to an experienced repair shop or boat yard.
Remove any seats or accessories as needed to fully access the damaged section of the boat floor. Pull back the carpet. Remove hatch covers or cabinet doors that may provide additional below-deck access at the area of the damaged floor. Disconnect and remove electrical wires and water lines below deck in the area of the damaged floor.
Mark a rectangular outline around the damaged section of the floor. Drill a 1/4-inch hole at the corners of the outline to insert the jigsaw blade into the floor. Cut the mark that outlines the damaged section of the floor and remove the section in one piece.
Cut two pieces of 5/8-inch thick marine plywood 4 inches wide and the length of the longest sides of the rectangular cutout in the floor. Drill 1/16-inch pilot holes about two inches apart along the edges of the cutout opening in the floor. The holes should be 1 inch from the edge of the cutout.
Use the cordless drill and start stainless steel wood screws in the pilot holes on the floor. Apply marine adhesive to the face of a 4 inch wide piece. Hold the piece in place against the underside of the boat floor so that it spans the length of one side of the opening with 2 inches of the long edge exposed.
Use the cordless drill to drive the stainless steel wood screws and secure the piece at the underside of the floor. Apply marine adhesive to the other 4-inch wide strip of plywood. Hold it in place at the opposite side of the opening with 2 inches exposed. Use the cordless drill to drive the screws and secure it in place.
Measure and cut two additional 4-inch wide pieces of plywood that span between the exposed plywood pieces at each end of the opening. Use marine adhesive and the cordless drill with stainless steel screws to attach these at each end with 2 inches exposed in the opening. This makes a four-sided mount for a repair patch.
Place the damaged cutout section of the floor on a piece of marine plywood and mark the outline of the piece. Cut the outline to make the repair patch. Drill 1/16-inch pilot holes one inch from edges of the repair patch and start stainless steel wood screws in each hole.
Reconnect the electrical wires and water lines below deck. Set the repair patch in place and use the cordless drill to drive the screws and complete the repair patch. Replace the carpet or use a fiberglass repair kit to finish the surface of the floor.
The length of the wood screws is equal to the combined thickness of the floor and the marine plywood. Add thin strips of wood under the edges of the repair patch to make it flush with the floor of the boat. Plywood bulkheads can be added as additional support for the floor.
Take the proper precautions when working near fuel tanks.