How to Remove and Replace a Wood Porch Column

Using a hydraulic jack to lift a porch beam to replace a rotten column.
Using a hydraulic jack to lift a porch beam to replace a rotten column.

Exterior wood porch columns can deteriorate and rot over time due to exposure the elements. Replacing a damaged porch column isn’t that hard, but proper safety precautions need to be taken to avoid injury or damage to the porch.

To remove and replace a porch column:

  1. Attach a short 2”x 6” board to the end of a 4” x 4” post.
  2. Position a jack directly under the porch beam next to the column.
  3. Measure from the porch beam to the jack, and cut the 4×4 to just under this length.
  4. Position the post, and use the jack to raise the porch beam slightly until the old column can be removed.
  5. Check to make sure the porch beam is level by raising or lowering the jack.
  6. If you’re using a plinth block as the base of the column, position it in the same location as the old column, then measure from the top of the plinth block to the bottom of the porch beam.
  7. If you’re installing the new column directly on the porch floor, measure from the floor to the beam.
  8. Make sure one end of the new column is square, and cut the column square to length on the other end.
  9. If the bottom end of the column isn’t sealed, paint or apply sealant to it to prevent water from wicking up the column.
  10. Attach the plinth block to the sealed bottom of the new column.
  11. Set the new column in place in the same location as the old column.
  12. Use a level or plumb bob to make sure the column is plumb in all directions.
  13. Slowly release the jack to lower the beam onto the new column.
  14. Apply optional trim molding to the base and top of the new column.
  15. Prime and paint the column and molding with quality exterior paint.

Watch this video to find out more.

Further Information

Exterior wood columns are often subject to water damage because of the exposure to the elements, but replacing them can be a simple chore. We’re tacking a piece of two-by-six onto one end of this four-by-four, which we’ll use to raise the beam that’s resting on the column.

A hydraulic jack beneath the four-by-four supplies the lifting power to raise the beam. For safety it’s important that the jack, post, and beam are aligned one directly over the other. With the weight removed, the rotten column can be removed.

The new column here is made from pressure treated lumber and will rest on a metal plinth block, so we measure from the block to the beam to determine the length of the new column before cutting it. This hollow, laminated column has a special factory sealant on each end. Since the sealant was cut off on one end, we’ll make that the top and attach the plinth block to the end with the sealant.

The new column goes into the same location as the old one. With the top in the corner, we move the bottom in and out and side to side until it is perfectly plumb. Then we slowly release the jack so the beam rests on the new column.

A few pieces of trim cover the metal plinth block and the whole thing gets a coat of primer and two coats of paint before it’d done.