A Building Guide for Porch Railing

Components

• A railing consists of a few different parts that all fit together to form the finished product. The balusters are the upright boards that run between the bottom rail and the hand rail to form the balustrade. And the hand rail and bottom rail are the horizontal boards that secure the balusters. At approximately every 72 inches a post is required as further support for the balustrade and sometimes has a decorative cap on the top. The post can rest of the bottom rail or the floor of the porch. The column is an integral part of the porch as it supports the roof. It runs vertically from roof to floor and becomes part of the railing.

Placement of the Posts

• Before you start in with the physical labor, you need to take measurements and make some calculations. Use a tape measure along the perimeter of the floor of the porch to determine where the posts will be located. The columns are already in place supporting the roof--they actually count as posts-so use them as starting points from which to measure. Mark spots approximately 72 inches apart, allowing for the dimensions of your posts. The goal is to keep the posts evenly spaced. Another method is to measure the distance between columns and place a post in the center.

Measuring the Balusters

• To determine how many balusters you will need between each post, add together the measurement of the width of your balusters and the gap between each. For example, if you are using 2-by-2 inch boards--which actually measure 1 1/2 inches--and a gap of 4 inches, the total is 5 1/2. Then you measure the distance between two posts (68 1/2), divide that by 5 1/2 and round up. This will determine the number of balusters needed between posts (13).

Placement of Balusters

• After determining how many balusters you need between each post, the spacing distance is the next measurement needed. Even though you used a 4-inch gap in your calculations for determining the number of balusters, this is not accurate for spacing. Multiply the width of the baluster (1 1/2) by the number of balusters (13) for a total of 19 1/2. This figure is subtracted from the total distance between posts (68 1/2) to arrive at 49. The number of spaces is always one more than the number of balusters, so divide 49 by 14 to get 3 1/2 and that is the size of your spaces.