How to Replace a Load Bearing Porch Column or Post
In the course of the lifetime of a house it may have to undergo major repairs. One such repair is a front porch column. If there is a damaged column holding up a front or back porch, a significant wind or storm could cause it to fail and bring the entire roof down. Replacing a broken column is a relatively easy job as long as you have the right tools.
Things Needed to Replace a Porch Column
- A friend
- Safety Glasses
- Work Gloves
- Roof Jack
- New Column and Securing kit (flanges and screws)
- Adhesive (Wood Glue or Contact Cement)
- Screwdriver (or Drill with Philips head attachment)
- Small wood plank
Jacking Up an Existing Roof
Before replacing a porch column with a new one, you first have to remove the old one. Because the column is likely supporting a heavy roof structure, a temporary support will need to be used. How to raise a porch to replace the column is a matter of choice. A roof jack is the best choice for this job, although some people choose to use 2x4s. 2x4s would need to be cut to size (an inch or so longer than the column) and then hammered into place. A roof jack, besides being more sturdy, doesn’t need to be hammered into place and therefore won’t cause any extra damage to the underside of the roof.
Some porch columns are not weight bearing and are more for show than for actual support. The only columns that are sure to be load bearing are those at the corners. But because there is no way to tell if the column is load bearing or not, it is best to err on the safe side and brace any column with a temporary support before attempting to remove it.
When jacking up the roof jack, place a small plank of wood between the top of the jack and the roof, to give more surface area for the jack to distribute the weight. If there is a weak spot in the roof it is less likely to fall if the weight is dispersed over a larger area. After the temporary roof support is in place, use the chalk to mark the footing of the column, as well as where it attaches to the roof. These will be reference points for the installation of the new column.
Removing the Old Porch Column
If your column is attached to a railing system, you will need to detach the rail from the column to proceed. If the rail looks like it will break due to the amount of play necessary to move it then place a brick underneath it for support until it can be reattached to the new column.
Removing the old column can be done in several ways. The easiest is to first remove any casing or trim at the base and top of the column. These pieces may have been secured with wood glue, or nails, or both. A crowbar works quite well to dislodge these pieces. Removing these casing pieces should expose a flange that connects the column to the roof and porch. Most flanges are held in place by Philips head screws. Once these are removed the column should move easily. If it doesn’t then there may be wood glue between the top of the column and the roof. This can be taken care of by cutting the column away from the roof with a reciprocating saw. There may be a similar problem at the base that can be handled in the same way.
Aligning and Installing the New Column
Once the old column is removed, clear away any debris from the area so that the new column adheres to the porch and roof without incident. Check the area where the column was attached for signs of wood damage. If there is further damage it will need to be taken care of before the new column is put into place.
If you are using a replica of the original column, move it into place using the chalk outlines as a guide. If you are not using a column of the same size you’ll need to find the center of the old column. To do this on a square base, simply draw diagonal lines connecting the opposite corners of the square together. Where they cross is the center. On a circular base draw a square around it using a carpenter’s square. Find the center of the new column in the same way. Align the new column with the help of your friend, one of you bearing the weight of the column, while the other slips the column into place.
Tips and Tricks
When you replace a porch column, the entire process should take no more than a couple of hours. The vast majority of this is removal of the old column and cleaning the area before installing the new one.
Make sure that you have a sunny day with relatively low humidity. The higher the humidity the longer it will take for the wood glue (or contact cement) to dry.
Also be sure to keep people away from the area while you are working. If there is a structural problem with the porch roof, removing the column may cause it to come down. Anyone not paying attention is likely to get hurt if this occurs.
Check with your local government authority to make sure that replacing a porch column does not fall under any special work codes that will require a permit. If you do replace the column without a permit in an area where one is needed you may be subject to municipal fines.
As always, use safety glasses and work gloves when doing any type of demolition or construction work.
Secure the New Column
Glue the column to the porch using wood glue (if the porch is not wooden then contact cement can be used). Once the glue has become tacky, attach the column flanges with Philips head screws. Do the same for the roof.
Once the flanges are in place add the casing trim and secure it with finishing nails. The nail holes may be filled in with putty or wood glue and then painted over while painting the new column to match the porch.