Floor Joist Cross Bracing Has Moved

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.

Floor joist cross bracing has moved.

Figure 1 cross and solid bridging with load on floor. I would say about 50 of the crawlspaces i inspect have cross bracing installed between each joist but never compleated. Would you consider this an issue after 30 years of no problems and would you recommend they be finished. Bracing will stiffen a floor system prevent floor joists from twisting and increase overall stability however there are actually two types of floor joist bracing commonly used.

Install with two 6d common nails per end. As shown in figure 2 it is not unusual especially in new homes to find that the cross bridging has not been nailed to the bottom of the floor joists. Bridging or x bracing allows joists to share weight. Simpson strong tie tension bridging galvanized steel the ltb s are used in floor systems to resist the overturning of floor joists and features a staggered nail pattern.

As a footstep falls on one joist some of the force is transferred to neighboring joists. Meaning the top end was nailed but the bottm ends were not. Figure 2 incorrect installation of cross bridging. How to brace your floor studs.

I have also observed that no twisting or movement issues were found and many homes are 20 years or older. Thd sku 205173.