How to Replace a Plywood Subfloor Due to Rot
- 1). Protect yourself during this job. Wood splinters can cause serious injury so wear safety glasses and gloves. Also, wear long sleeves and long pants.
- 2). Pry up the plywood. Start in one corner. Insert your prybar underneath the first sheet of plywood and pry upward. Where you see a nail, you will need to pry the area up. If the areas are too rotten to pry, remove what you can by hand, and use a handsaw to cut away bad areas. Work until all of the rotten wood has been removed. Keep a large garbage can next to you as you work to make the removal easier.
- 3). Remove any remaining nails. Use the other side of your hammer, or a nail removing tool and go over all of the floorboards removing any nails that were left behind. While you are doing this, check the joists to ensure they were not affected by the rot.
- 4). Lay down the first sheet of plywood. Start in one corner of the room. Insert a nail through the plywood into the joist at a rate of one per every 12 inches. Continue until the first sheet is secured and move to the next sheet. A nail gun makes this process go a lot faster. Make any necessary cuts in the plywood with a circular saw.
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