Beam & Post Construction Techniques

Beam and post construction utilizes a framework of horizontal timbers known as beams and vertical timbers known as posts.

Post and Beam Construction

The framework pieces are joined by mortise and tenon joints. This construction method is centuries old. It produces strong structures that in some cases have remained useful for more than 100 years. Buildings built with a post and beam technique are visually appealing and have a solid and substantial appearance.

Post and beam construction requires time and carpentry skills. Each joint--a connection between two or more timbers--requires the carving of the mortise and tenon.

The mortise is defined as a square hole in the end of a timber designed to receive the tenon of another timber. Each of these components is individually carved to fit with the other. Some carpenters finish the mortise and tenon joint by drilling a hole through the joint and driving a wooden dowel into the hole. This creates a joint without the use of nails or other metal fasteners.

In traditional post and beam construction, the timbers are left exposed on both the exterior and interior of the building. The spaces between the posts and beams can be filled in with lighter building materials as these segments of the walls do not carry any of the weight of the building.

In some modern post and beam buildings the exterior walls cover the timbers, leaving the wood posts and beams exposed in the interior of the building. The design can be reversed, with the interior of the timbers being covered and the structural elements left exposed on the exterior. Either design is structurally sound and the choice is a matter of aesthetics.

Post and beam construction offers a number of advantages for builders with the skill and time to devote to the project. The timber frame makes up the weight-bearing portion of the structure. While interior walls can be constructed to divide rooms, they are not structurally necessary and can be placed as desired for the floor layout.

Post and beam construction techniques work well for the construction of large buildings like houses and barns and also small structures such as a tool or garden shed. The same carpentry skills and techniques apply in projects of any size.

About the Author

Keith Allen, a 1979 graduate of Valley City State College, has worked at a variety of jobs including computer operator, medical clinic manager, radio talk show host and potato sorter. For over five years he has worked as a newspaper reporter and historic researcher. His works have appeared in regional newspapers in North Dakota and in "North Dakota Horizons" and "Cowboys and Indians" magazines.