How to Fix a Porch Support Post

Measure the distance from the base of the porch post to the point where it touches the porch roof, using a tape measure. If needed, use a ladder so that you make accurate measurements.

Lay a two-by-four on the ground and mark the same distance you measured, using the tape measure and a pencil. Place the two-by-four where you can cut it safely. Don safety glasses and cut the board along the pencil line, using a power saw.

Stand the board up vertically and place the bottom on the porch approximately 12 inches away from the damaged post. Place a level on the board to ensure that it is straight up and down. Tap the top using a hammer to wedge it under the porch roof.

Place the ladder next the post. Insert 3- to 4-inch-long screws up through the top of the post at an angle, using a power drill. Make sure that the screws penetrate the roof material to hold the post to it. Insert at least four screws around the perimeter of the post.

Examine the post from the bottom up. Draw a line around it above the damaged section. Cut through the post at the line, using a reciprocating saw.

Remove the damaged post section and lay it next to a replacement post. Cut a new post section to the same length.

Apply a 1/4-inch layer of polyurethane caulk to the top of the replacement section. Insert the new post section under the post. Insert wooden shims under the bottom to raise it up to meet the upper portion.

Wipe off the excess caulk around the seam. Apply more caulk around the bottom of the column base to hide the wood shims.

Wait 24 hours to allow the caulk to dry completely. Tap the top of the two-by-four using the hammer to dislodge it from the roof and set it out of the way.