What is the maximum allowable spacing between floor trusses. All of them are 19.2" O.C. but one.?

Question

The builder is moving the truss to the side about a foot to allow plumbing to come through the floor so now that truss spacing is about 30" between them. He is using 3/4" OSB for the floor. Isn't this going to cause a problem? Please give me some good specific references to building code or product specs if you can. Thank you

Answer 1

Yes that is a problem. You could construct some stringers between the trusses perhaps as a fix. They could be 2 x 4's every 18" perhaps.

I would need more data for a firmer mitigation.

Answer 2

Simply refer to the (referred to) local building codes ... doesn't matter if the structure will hold the desired weight if the building inspector doesn't pass the structure.

The spacing between the trusses is irrelevant to plumbing the structure ... unless, of course, he is using pipes larger than 30" ... once again, the building code will state the minimum and maximum distance between the trusses and between the trusses and the associated plumbing.

Call the city and ask...

Answer 3

I would definitely rate it as a problem, and would re-jigger things so that it is not necessary to move the truss. But there is far too little data supplied here to come up with specifics (floor loading? truss span? truss size?), but if you use this data to go into the UBC, you could get the details you need.