Bouncy Floors

Originally Posted by greenley

The metal plates do not make an "x". They span from truss to truss and have tabs at each end for nailing to the wood.

Originally Posted by Mike772

I build with floor trusses, maybe I can help.

22' should be no problem for floor trusses. I've clear spanned 32' with no problems and zero bounce. Granted I had them at 16"oc, but the original plans had them at 24"oc, my point is they will be engineered for your application to work. By me reducing the spacing, I reduced the bounce.

Floor trusses don't require "x" bridging, atleast in my state. They do require strongbacks. Continuous 2x6's nailed to the vertical member (inside the trusses) of the floor trusses. So from truss to truss and so on, from one end of the house to the other a 2x6 nailed to the vertical member with a minimum of (3) 16d sinkers on each vertical. Check the paperwork that came with the trusses, there is usually an explanation and some graphics of what they want and what is required.

Now, on my larger spans I increase the the strongbacks to every 5', which is every vertical member in the truss. I'm told by engineering that will decrease deflection. And it does. I've noticed that any bounce or deflection to be almost completely gone when I add that many.

The real trick is to not let the other trades notch or cut up those strongbacks. Depending on the height of the trusses, it usually isn't a problem.