Pontoon boat decking is usually constructed of marine plywood screwed to the aluminum deck beams and covered with marine carpet. The bottom of the decking is subject to water damage from repeated exposure to spray from the pontoons when the boat is underway. Spray and rainwater can also accumulate on the upper surface, where it soaks through the carpet to the decking below. The carpet can also trap moisture that will produce mildew and mold, causing further weakening of the deck material. Replace damaged decking using commonly available materials and tools.
1. Remove the deck furniture, using wrenches. Save all deck furniture mounting hardware for re-installation.
2. Cut the edges of the carpet loose with a razor knife. Pull the carpet off the decking to expose the deck fasteners.
3. Remove the fasteners holding the decking to the deck beams, using a drill motor and screwdriver tip or nut-driver tip. Remove the decking from the boat.
4. Measure the width of the deck, using a tape measure. Crosscut the plywood sheets with a circular saw, if necessary, for a proper fit.
5. Lay the first sheet of plywood on the deck, starting at the bow. You want the edge of the plywood to fall in the center of a deck beam. Mark the plywood sheet at the center of the after-most deck beam that it covers. Remove the plywood and rip it to width on this mark.
6. Place the first sheet into position and repeat the process until the entire deck has one layer of plywood covering it. Make certain that the deck beams support all of the joints in the plywood.
7. Lay the first sheet of the second layer of plywood on the deck, starting at the bow. Mark the sheet for a rip-cut so that there is a 2-foot offset from the joint in the first layer.
8. Lay the subsequent sheets out to cover the deck with a second layer of plywood. Trim the width of the last sheet to fit, using a circular saw. Remove and stack the plywood in the order that they were laid.
9. Paint the bottom side and edges of the first layer of decking, using marine paint and roller, and allow it to dry completely. Lay the first layer of decking in place and fasten it to the deck beams with marine-grade self-tapping screws, using the drill and screwdriver tip. Place the screws no more than 12 inches apart to ensure a good connection to the deck beams.
10. Paint the edges of the second layer of decking with marine paint and allow it to dry completely. Lay the second layer of plywood in place over the first and screw it down with 1 1/4-inch marine-grade screws.
11. Paint the top layer of decking and screw heads with marine paint. Allow it to dry completely.
12. Stretch marine carpet over the decking and staple it securely in place with a staple gun. Trim any excess carpet, using a razor knife, after the carpet is secure.
13. Place the deck furniture in position and drill through the decking, using the mounting tabs as a guide. Bolt the deck furniture down securely with its original hardware.
Items you will need
- Wrench set
- Razor knife
- Drill motor
- Screwdriver or nut-driver tip set
- Tape measure
- 1/2-inch marine plywood
- Circular saw
- Marine paint
- Self-tapping marine grade screws
- 1 1/4-inch marine screws
- Marine carpet
- Staple gun
- Using marine adhesive between the deck beams or the layers of decking may give the deck some extra rigidity, but you will also complicate the deck replacement process, if needed in the future.
- Avoid using epoxy and fiberglass resin and cloth, as it will add substantial weight to the decking, and will reduce the safe carrying capacity of the boat.
- Capt. TJ Hinton; Commercial Fisherman; Gulfport, Mississippi