Bridging Floor Framing

If you look at typical wood floor framing you will often see rows of cross bridging between the floor joists.

Bridging floor framing.

Note also that wood is a natural material with a lot of variability in e. The floors of most modern structures are built by arranging individual pieces of dimensional lumber in a consistent repeating pattern. For longer spans two rows of bridging spaced 6 feet apart are required. Bridging distributes the load to the stiffer joists.

Bridging allows each joist to share weight with its neighbors and can cut deflection how much the joists flex by half. 406 or 610 mm o c. It also helps make sure concentrated loads are shared between multiple joists. The catch of course is that the bouncy floor joists must be accessible from below.

This process commonly known as stick framing results in a structure that s lightweight and economical yet built to last. It also will help even the floor out and restrains the wood joists as they twist and sag as they dry out from the installed moisture contenet of about 19 to the equilibrium value. Bridging takes a lot of the bounce out of the floor under foot traffic. If it is wood it is nailed to the upper top of the side of the floor joist before the floor or sub floor is installed on the joists.

Even if your floor already has a row of bridging running down the center you can stiffen it substantially by adding two more rows. Ez x bridging will help eliminate the floor from flexing and squeaking install easier look cleaner and also save labor installation costs learn more about. Otherwise many panels will have to be cut wasting both materials and time standard joist spacings are 16 or 24 inches o c. It is usually required when the joist spans are more than 8 feet.

Stands for on center meaning that the spacing is measured from center to center. Floor framing figure 5 19 is laid out in such a way that the ends of un cut 4 foot by 8 foot 1 2 m by 2 4 m subflooring panels will fall directly over joists. Attaching the bottom portion of the cross bridging to the joists should be done after the flooring is installed. Bridging holds the joists in line and helps distribute the load carried by the floor unit.

The bridging helps prevent joists from twisting when they re loaded.