Cross Support For Floor Joist

A joist support is the horizontal beam that supports the floor joists.

Cross support for floor joist.

Most decks use 16 on center spacing for joists. 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. 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. Most decking is not strong enough to support longer spans than 16.

Cross bracing or bridging is another system that reinforces a structure of a building just like blocking does. You can use cross bracing instead. Recommended beam joist spans for deck framing. The layout term for joists is on center which is the center to center measurement from one joist to the next.

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. The joist support helps reinforce the floor so it can handle the weight load it needs to. Solid blocking should be used where floor joists overlap over beams. It should be placed at eight foot intervals between any floor joists 2x10 or longer.