Acceptable lateral support for ceiling joists?

Hello all,

I’m having a house built in Spring, TX and I hired an inspector to come through and make sure everything was on the up and up.

One of the first things he noticed was inadequate lateral support for the ceiling joists in the garage. Picture below.

I took this to my builder and asked that he install the bridging my inspector recommended. My builder said to me that he’s going to install a “strong back” on top of the joists in the center of the garage according to R802.8.1 (I’m no expert, but I can’t see any reference made to such a feature when I looked up the code). I went back to my inspector and reported what my builder said, who replied that a strong back isn’t a substitute for bridging.

What is correct? Is a strong back or “rat run” adequate for lateral support? I appreciate your input.

R802.8.1 Bridging. Rafters and ceiling joists having a depthto-
thickness ratio exceeding 6 to 1 based on nominal dimensions
shall be supported laterally by solid blocking, diagonal
bridging (wood or metal) or a continuous 1-inch by 3-inch
(25 mm by 76 mm) wood strip nailed across the rafters or
ceiling joists at intervals not exceeding 8 feet (2438 mm).

I do a lot of phase inspections in Greater Houston area. I rarely see blocking anymore. What the builders typically do is place a 2x4 on its wider size, on top of the joists and a 2x6 on its thinner side butted up against the 2x4, which creates the “strongback”

Bridging for sure. Solid or diagonal. Not talking about code just quality. 8’0 oc min.

Those joist are too big for a normal garage roof rafter. Is this a extra wide garage or do you plan to use the attic area as a room?

Those are very common around here. Typical for a 2 car garage (which is the norm here). No room upstairs, just empty space.

I saw that too. Looks like the ceiling joists are sized for a storage floor or future room. If used as a floor, I would use bridging. If just for ceiling joists, a rat run is fine. What do the plans say??

Thanks again for your input. The builder won’t give me the plans, so I have to take him at his word. I went back yesterday and saw that they put up one strong back, but with your comments I asked they install a second one since the garage is 20 feet wide. This is what they put up:

If y’all are good with it, I’m good with it. :slight_smile:

I hear the big attics are called “Texas basements” so, everything is bigger here I guess!

I agree, needs more than one run for that span. Those standard lumber joists will try to warp and pop your drywall nails, without proper bracing. I would install at 48" OC or sheet with plywood.

Yes, 8’ apart would be needed around here for that but we typically like bridging/blocking…different in different parts of the country and depending what it is used for.

Gordon, I’m not good w/ it. this in reference to your statement above… You’ve got the strongback laying on top of the ceiling joists in your last pic, but how well are they fastened? There’s obviously no fasteners up from joists to the strongbacks as seen in pic. Even if strongbacks are properly fastened from above and down into, which we can’t even verify from pic that is from below, the joists should have fasteners up thru them into strongback(s) to help w/ future seperation. Nails (unthreaded like screws) pull apart, that’s why they should be nailed from both sides, for instance just as joist and rafters connections should be nailed together on both sides that are sitting on an exterior wall- to help prevent seperation.

See image below-

Here is the image I use for strongbacks on my framing (predrywall inspections) in my reports.

Hey Joe! How’s it going in San Antonio? Long time no see around here
I’ve got to get down there so we can grab a few drinks (coffee or/and beer) :smiley:
Hope the phase inspections are keeping you busy. It’s been crazy around this part of TX

I think you’d have to do it like Joe says, or use proper bridging to prevent twist. A rat run on top may prevent separation, but not twist.

Hey Will, going good. Can’t wait for it to cool down some though. Getting old being high 90’s or 100 every day. I know you have it about the same there in Htown.
Mike, I don’t feel that a rat run will help as much w/ deflection / sagging as will a full strongback.

concurred, Joe, thanks! How the heck ya been? I thought ya mighta fell off the face of the earth!

Been doing good Mike thanx. How’s my favorite Hillbilly doin ? :smiley: :smiley:

Business is growing a little, Joe, but the bills and the headaches seem to be keeping up a good pace!! :|.)