Cross Support For Floor Joist

Most decking is not strong enough to support longer spans than 16.

Cross support for floor joist.

Recommended beam joist spans for deck framing. A joist support is the horizontal beam that supports the floor joists. Figure 4 2 x 4 installed below duct work table 1 provides the correct quantity of bridging relative to the span of the floor joist. 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.

Cross bracing or bridging is another system that reinforces a structure of a building just like blocking does. The bigger you make your deck the more you ask of the framing timbers that hold up the deck s structure and the joists and beams that support the. Solid blocking should be used where floor joists overlap over beams. Providing more support and rigidity than cross bracing solid blocking is a reasonable alternative but can be an obstacle for running plumbing pipes and electrical wire between floor joists.

Although not as good as solid or cross bridging a 2 x 4 supporting the duct work as shown in figure 4 would provide more support and load sharing than a light piece of metal. In some cases additional joist supports will have to be installed before there can be extra heavy objects on the floor. The joist support helps reinforce the floor so it can handle the weight load it needs to. Most decks use 16 on center spacing for joists.