Wooden Porch Repair: How to Replace Boards

A standard wooden porch floor is normally installed using tongue and groove flooring pieces. This means that if you plan to replace any of this type of flooring with similar flooring, you'll need to use special removal techniques and tools; otherwise, you are likely to damage your good flooring materials and not be able to re-use it. This is true whether you're removing disintegrated or rotten flooring, or if you are planning to replace existing flooring with a different material.

Tools and Materials

  • Circular saw
  • Pry bar
  • Hammer
  • Nail puller

Step 1 – Preparing Your Replacement Boards

Before removing damaged or rotted floor boards, plan to treat your new boards to make them impervious to insects or fungi that can damage your new boards. To treat your boards, make a mixture of water and a chemical that is boron based. Place this solution in a tray long enough to hold your new boards. Submerge your new boards in this solution until they are soaked, then, remove them and allow them to dry while you're removing the floor's damaged boards.

Step 2 – Cut and Paint or Varnish Your New Boards

Once your boards have dried from being in the boron-water solution, cut them to the length you'll need. Then apply paint to all surfaces of these boards, including the cut ends. Be sure to avoid paint buildup in the tongue and groove spaces. This paint buildup can prevent fitting these boards together properly. Allow the new finish to thoroughly dry (about one week) before installing them.

Step 2 – Cut Center Strips out of the Damaged Boards

Removing old tongue and groove boards can be tricky if you want to retain your floor's good, usable boards. To remove them without damaging good boards, use a circular saw and make two cuts down the length of the board you're removing. Before making your cuts, set your saw blade to make a shallow cut, about 1/16 inch deeper than the board's thickness. Make each cut about ¾-inch in from the edge of the tongue and groove of the cut board and parallel to these edges.

Step 3 - Remove Damaged Boards

With the center strip removed from the board, place the edge of a pry bar or edge of a large straight edge screwdriver into the joint between the board you're removing and the board next to it. Tap the pry bar hard enough to push the remaining edge of the cut board into the center and away from the secured board next to it. Use a nail puller to remove the nails and all wood remnants.

Step 4 – Installing New Boards

To install your new boards, slide the board into place next to another board so that the tongue of one board fits into the groove of the one placed against it. If necessary, tap it tightly into place. To hold it in place, drive finishing nails through the groove on the free side of the board. Repeat this with all new boards you install. When finished, paint or varnish the entire floor.