Thorough reinforcement is a critical part of construction projects. In some instances, such as with home building, reinforcement specifications are mandated by state and local building codes. Two common types of reinforcements are ledger strips and hangers. Determining which is safest to use in a given project and any surrounding legal requirements is an important part of your construction planning.
What are Ledger Strips?
Ledger strips are boards nailed to the side of a beam to form support for joists. The ends of the joists would be flush with the ledger strip. In general, the use of ledger strips is accompanied by strict regulations.
For instance, the International Residential Code, which differs by state and locality, indicates in section 502.6.2 of its New Jersey code that "Joists framing into the side of a wood girder shall be supported by approved framing anchors or on ledger strips not less than nominal 2 inches by 2 inches."
Ledger strips are less supportive than joist hangers. They are often used for projects involving the support of horizontal surfaces like decks or cabinets. They are not ideal for whole house construction because they do not defray as much force from the joists and are more likely to fail via breaks or falling.
What are Joist Hangers?
A joist hanger is an inexpensive, u-shaped metal bracket that supports joists, anchoring them to a ledger board. A ledger board — a flat piece of timber anchored to the frame that evenly spreads the load of the joists it supports — is used for the installation of hangers.
Joist hangers help to keep joists anchored over time and absorb the forces of the structure above. They offer a higher level of protection than ledger strips due to their shape and material, and are therefore preferred for heavy-duty construction. The American Wood Association recommends that joist hangers be made of galvanized or stainless steel.
To determine the size of the joist hanger needed for your project, consult planning guides or construction resources whenever possible. Hardware or home improvement store associates may be able to guide you in the right direction as well. Sizing is highly project-specific; for instance, if you are building a deck, joist hangers should have a depth of at least 60 percent of that of the attached beam.
When to Use Which Support Type
Joist hangers should be used whenever possible. They provide a simpler, inexpensive and stronger method of reinforcing your joists. Building codes often require joist hangers due to their better performance.
Ledger strips are more aesthetically pleasing than joist hangers, hence their widespread application for cabinets and other visually prominent areas. If you are considering a ledger strip for visual reasons, consult your local building code before doing so.