How to Install Balustrade Systems up to Round Porch Columns
Many people purchase a balustrade system that will be installed into their round porch columns. This can present a challenge of having to install a balustrade railing, which has square ends, into a round porch column. So how do you do this? We have put together these five steps on how to attach a rail to a porch column to help you get around this challenge.
The "V" cut and Routing method (Skill level 5/5)
Step 1 - Measure the inside dimension     between your porch columns. You will need to mark the top and bottom rail with a measurement 3/8” less than the distance between the centerline of the two porch columns. Take in mind that the bottom rail may actually be a shorter distance than the top rail if the round porch column is tapered.
Step 2 - Once this measurement is known take a table saw or circular saw and cut a “V” leading up to the marked point in the center of the rail.
Step 3 - Take a router and round the edges of the “V” to accommodate the curvature of the column. This will take some time and you must be careful when cutting.
QUICK TIP: If you have just installed the porch columns you may able to obtain a small section of the column to use as a template. You may also know the diameter of the column and can create a paper template which would allow you place on top of the rail and trace to show the curvature of the column.Â
Step 4 - After you have the rail properly cut and curved it is time to install the rail, along with the proper mounting hardware into the round column. Start by installing the bottom rail first, then the balusters, and finish with the top rail on top. You can shim the rail on both sides along with adhesive to help hold the rail in place.
Step 5 – Once installed and the adhesives have dried you can then caulk the joints and then paint over the caulk and this will leave you a finished rail running into your porch column.
If you have any questions please make sure that you contact an architectural specialist or hire a skilled carpenter when attempting this method of installation. This does require a great bit of skill and with that requires experience and craftsmanship in order to have a successful installation.