Porch columns and porch posts support a beam that supports the porch roof.
This may sound very simple but this is a crucial area that is frequently done wrong by carpenters today.
The design is actually very simple yet carpenters continue to mess up a good design.
Here we will discuss two basic types of porch supports: columns and posts. Entire books are written on this subject which is quite complicated but here I will show you the basics you need to know to avoid making common mistakes.
Columns are round and piers are square but we will use the term column interchangeably here. Porch posts however are narrower and the wood is usually turned – exclusive to Victorian homes.
Round columns are based on the Classical Orders of Design. There are features a column must have and strict rules for their exact location. There are formulas to determine the correct proportion based on the height of the column. There must not be any deviation from the rules of a properly designed column. Reputable manufacturers will state that their columns are “architecturally correct”.
Turned Victorian porch posts do NOT have strict rules although there are good and bad designs but that is not important for this article.
Starting from the bottom. The base of the column or post must be no wider than the porch pier supporting it.
The top of the column or post must support the base of the porch beam and the shaft of the column or post must be exactly the same diameter of the beam. No exceptions.
This is 100% WRONG. The contractor and architect both should end up in a medieval prison in a cold climate.
Turned porch posts line up the same way but the porch beam is not as wide. If your original porch posts are missing, you must have new posts milled with the top portion that is square – not turned be the same width of the porch beam. This is an easy way to determine the size of the original posts.
Please ignore the vinyl bead board. I will find an example on a nicer house.
Here is a very good video by Brent Hull on Building Tapered Columns.
You can’t explain it better than this!
The following books are companion books and I recommend purchasing both of them. You will be very happy you did.