How to Repair a Rotten Wood Floor in an RV

Remove all cabinets or benches that may be sitting on top of rotten wood. For an ideal fix, it's important to replace rotten wood underneath furniture so that the pieces won't sag down and cause more damage. After all the structures are out of the way you can begin removing the tile or vinyl flooring. If there is water damage it is likely that the dampness will have loosened the adhesive. You may need to use a scraper to dig underneath the tile and pry it upwards. Discard of all water-damaged material.

Use a reciprocating saw to remove the particle board from the floor. If there is only a small area of water damage, you can simply cut a rectangular hole in the particle board around the damaged area. If the rotten area is wider and spans the width of the RV, it may be necessary to cut up against the wall. Be careful not to let the saw reach the metal siding of the RV. Cut a straight line separating the good flooring from the rotten wood. This will make it easier to replace once the rotten material is removed.

Remove all Styrofoam insulation that may have been damaged. Use a scraper to remove all the remnants of flooring and Styrofoam and vacuum the area clean. It may be necessary to add extra beams into the floor to provide more support. If the beams of the floor have been damaged or become rotten, they may also need to be removed and replaced. If there are any rust spots on the floor base or wood beams, paint over them with quality, water-resistant paint to prevent further damage.

Lay fiberglass insulation pads between the floor beams to provide a better heat seal within the RV. This will also keep pipe and wood temperatures stable to prevent further water damage. Cut the new plywood flooring to fit the area that you removed the rotten wood from. Mark on the plywood where the floor beams below it will lie. Lay the plywood in place and screw it directly onto the floor beams.

Replace the flooring. Ceramic tile is not recommended because it will add extra weight and unlikely withstand the flexing of the RV during transport. Use stick-on tile or carpet to recover and a carpet bar if necessary to hide the separation line between the new flooring and the old.