Understanding the Anatomy of a Wood Frame Floor

It is important to understand the anatomy of the wood frame floor for several reasons that include knowing how to properly install plumbing and wiring. It is also necessary when determining what types of appliances and pieces of furniture are safe to put on top of it. There are several materials put together to create the frame. As long as you get a basic understanding of these parts, then it is easy to get to work with them in the future.

Joists and Beams

The joists are the wooden beams that support the entire floor. These are made out of solid wood that have dimensions of either 2 by 8 square inches or 2 by 10 square inches. These beams are usually 16 inches in length and are positioned in 90 degree angles between the supporting beams and/or walls. The ends of the joists are fastened securely to the beam as well.

The beams are made of either solid wood or metal. These supports are installed to bear the entire weight of the floor including the load on top of it.  All beams are further supported by the joists.

The Subfloor and the Underlayment

The subfloor underneath the main wood flooring is made of plywood. The layer of plywood is set by most local codes to be 5/8 inch thick or more. This layer of flooring is required before installing the main flooring. When the main flooring is made of certain hardwood floors or laminate material, an underlayment is required. An underlayment is a moisture barrier that prevents molds and mildew from growing. These layers also provide floor insulation and help level the floor surface. It may also prove helpful during the installation of the main flooring.


Adhesives are used to secure certain types of flooring material such as wood tiles. These adhesives can either come with wooden tile installation kits or purchased separately. Therefore, the adhesives can be made out of different materials such as urethane. These adhesives are only applied to clean oil-free surfaces. When the surface of the subfloor or underlayment is not properly prepared, then the adhesive will not be able to stick well.

Main Flooring Material and Coverings

The main flooring material for the wooden frame floor can be made out of many different types of wood or other flooring materials such as OSB, laminate flooring, or even ceramic tiles. The main flooring is the surface most susceptible to stains, scratches, and damage. Therefore, it is important to use flooring materials that are durable and of high quality.

When the all other parts of the floor are installed, the surface of the main flooring material can be covered with carpets, rags and other protective covers. The rags and carpets do not only provide extra protection, but add to the aesthetics and design as well.

Floor Loads

The furniture, appliances, pipes, ventilation and other fixtures also form a part of the wooden frame. These form the load that is supported by the frame. It is important to take note of the load capacity of the frame to ensure that it does not get damaged easily.