Adding Cross Bracing To Floor Joists

Cross bracing and solid blocking.

Adding cross bracing to floor joists.

Residential building code requires the use of cross bracing or blocking for floor joists exceeding 2 inches by 12 inches but many homes especially older ones have creaky uneven floors because. Even if your joists already have a row of bridging at the center of the span adding a row on each side of the existing bridging will stiffen the floor. Bridging or x bracing allows joists to share weight. However there are actually two types of floor joist bracing commonly used.

Bracing will stiffen a floor system prevent floor joists from twisting and increase overall stability. This can allow for floors to be sturdier and more stable. 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. Cut a piece of 2 by 6 or 2 by 8 lumber according to the width.

Nail the block in place with 16d. The difference is that the cross bracing uses two pieces of support in a diagonal shape that creates an x between the joists instead of a solid block in blocking. As a footstep falls on one joist some of the force is transferred to neighboring joists. Because of this x shape one brace will be forced upon and under tension while the other brace will be compressed.

Measure the width between the span of two joists. A floor that bounces as you walk across it may just need to be stiffened with bridging which spreads the load on each joist to adjoining joists strengthening the whole floor. Continue reading below our video of the day.