How to Measure for a Column

Measure the opening you actually have, then read the drawing for that SKU. The families on the column types page do not share one height rule.

Height

Measure from the finished floor or deck to the underside of the beam at each column. Those heights often differ from one bay to the next. Write them down separately.

On a decorative CLM column, 96, 120, and 144 inches is the shaft only. The cap and the base add their own height. On a structural model, that number is the overall height, including the flanges.

Example for a decorative smooth tapered column: CLM100-10-8 is a 10 inch bottom, an 8 inch top, and a 96 inch shaft. CAP100-8 is 2¾ inches high. BSE100-10 is 5¾ inches high. 96 + 2¾ + 5¾ = 104½ inches assembled, before any trim. See column caps and column bases for the part numbers.

Diameter

A tapered column has two numbers. The first is the bottom. The second is the top. The cap matches the top. The base matches the bottom. A 10/8 column takes an 8 inch cap and a 10 inch base. A straight column uses one diameter, so the cap and the base are the same nominal size. Decorative columns and structural columns follow that same top-and-bottom rule.

Proportion

A taller porch and a heavier-looking beam usually want a wider column. A short entry can look top-heavy if you jump to the largest diameter. Hold the drawing up to the opening before you order. This guide does not set a diameter formula.

Cutting to height

Order the next shaft height up and trim it on site with a fine-tooth saw. Cut from the bottom of the column only. Never cut the top. On a tapered shaft the top diameter has to stay matched to the cap. Keep the cut square. The base covers the cut end.

The factory sequence is in the column installation instructions.

Shaft height helper

Enter the floor-to-beam height and pick a decorative or structural column, then a cap and a base whose heights are published for the size shown. The result is which of 96, 120, or 144 inches to order, and how much to trim. Cap and base heights change with the size. If your size is not in the list, use the drawing.