What is Post and Rail Fencing?

Post and rail fencing is a fence style that uses perpendicular posts driven into the ground with two or more horizontal rails attached between the posts. This rustic fencing style is often often seen at horse farms and around pastures. This type of fencing is traditionally made from wood, though synthetic materials are now commonly available. Post and rail fencing commonly is constructed from round or square posts and round or flat rails.

There are two primary construction methods for attaching the fence rails to the fence posts. A traditional and sturdy method uses mortises, which are holes cut through the fence post through which the rails are inserted. A cheaper but less durable method is to simply nail or screw the fence boards to the post; this method typically is faster as well. While mortises are more durable, they are also more time consuming and costly.

When using the mortise method of attaching the rails, both round and square posts are suitable. Holes are bored into the wood at the height intervals desired for the fence rails. The rails, usually cut narrower at the ends, are inserted into the holes in the posts where they rest without requiring any further attachment. Nailed or screwed post and rail fences require square posts that provide a large enough surface to secure the rails to the posts.

When constructing a post and rail fence, a line of post holes are dug, usually about 6 feet (2 m) apart. Rails 12 feet (about 3.6 m) long are nailed or mortised alternately to every other post down the line of the fence to create a continuous structure. The method of alternating 12-foot (3.6-m) rails between 6-foot (2-m) posts gives the rails suitable support to prevent warping and bending.

Post and rail is an open fence design that often is used to mark property lines and contain large animals, generally horses. Due to the open nature of this fencing style, post and rail fencing does not provide privacy or act as a wind block. Most of this fencing is made from either natural, stained, or painted wood. Pressure-treated or rot-resistant woods, such as cedar, are best suited for outdoor fencing. Other synthetic materials, such as vinyl, are durable alternatives to wood fencing.

Split rail fencing is a style of post and rail fence that uses narrow logs split lengthwise to create the rails. This fencing construction has a rustic look, as the rails tend to follow the natural lines of the log. In contrast, milled lumber used for many fences is consistent in shape and size.