Garage sheetrock ceiling question

[BBC71Nova]

OK question for you pros .

I'm gonna be finishing the interior of a detached garage for my parents. Typical stick frame construction. Ceiling is built of manufactured 16" I-joist on like 10-12" centers (can't remember at moment). It was built that way to support a room upstairs should the need arise in the future. Not in the current plan though.

I've done a fair amount (as a DIY guy) of sheetrock work over the years. A few years ago I read online about running furring strips across the ceiling joists prior to the sheetrock installation. The theory was it helped isolate movement, leveled out the span, etc yielding a better result over the long haul. It makes sense to me but I've never seen anyone actually do this in local construction.

What are your thoughts on this? It adds a fair amount of work/time to the project and a little cost for the lumber. Especially given I'd be screwing the 1X4s strips or whatever.

Thanks!!

 

[Aura]

If you have 12" OC (Which I have never seen) just rock it. My house has them 19" OC

 

[Nowater]

The furring strips allow one to level the ceiling if needed by placing shims between the joists and the furring strips. Some people use furring strips if the joints are 24" on center or if the joist layout does not match the size of the intended drywall. Some areas of the country always use furring strips, and consider it a botched job if they are not used.

BTW, it sounds like this is the time to isolate sound and to insulate for heat/cold.

You may be required to use 5/8" sheetrock for a fire break. I suggest you call the local building official.

Is there any need to run wires or pipes in that ceiling now? How about lighting for the garage.

 

[BFBOB]

Even if not required, use 5/8" FireCode drywall. It's a garage: sources of ignition y'know ... especially if they never bothered to take in their Ford to get the exploding cruise control fixed.
Since the garage is detached, it's probably not required NOW, but if that upstairs is ever finished, it will probably be classified as living space. Easier to be ready for it.

Oh, and rent a drywall lift. Dirt cheap for the amount of time/effort it saves, even if you have friends helping.

 

[JACDes]

No need to add furring to manufactured l- joist they are level.

FWIW, An accessory building (detached garage) does not need to be fire rated, even with an attic space above, it is not a habitable building because at the end of your tinker time you go back to the main house to eat, sleep, etc.

That being said if this was an attached garage with a habitable space above it (bedroom etc.) it you would have to drywall the garage ceiling with 5/8 gyp. bd.
The wall between the garage and home would also need to be fire rated.


For most detached garages 1/2" sheet rock is just fine but if you want 5/8 that's fine too.

 

[Whitworth]

I wouldn't bother using furring with engineered lumber products, but for regular 2 by lumber I would. 2 by joists are narrow and can be out of straight by a 1/2 inch or more, depending on blocking and how well it's executed.

Working overhead you want everything in your favor.

Gary

 

[BBC71Nova]

Thanks guys.

Yeah I need to get some pics. The joist seem crazy close to me. If I were to screw into each joist there'd be a lot of nail hole spackling to do.

I've already roughed in all the wiring too. Just gotta get moving on the rest.

I hadn't decided about the fire code rock yet. I thought it was required to separate any inhabited area from a garage area. Good to hear it would be acceptable to not use it due to the structure being detached. I may do it anyway though just be be safe.

 

[Aura]

I would go with the 5/8" but you still want to screw on every joist. If you screw off on every other one you are at least 2 feet apart and I think it will get wavy over time. I'm doing my basement so I feel your pain about muding overhead.

 

[dfiler2]

The 1x4's on the bottom of I-Joists are not used to "level them out" they are used to act like bridging. When you have a long I-Joist span, generally over 24' you may get some bounce on the floor as you walk across it, the bounce might be noticeable as you walk across the floor in the upstairs room. The joists meet code and are not a concern, people just don't like to feel the bounce. The sheetrock alone may take care of it or there may not be any noticeable bounce.

 

[Tdoriot]

Good advice above. As a 30 year custom home builder, Rock it with 5/8 and call it happy. You can fasten every other joist so it's fastened @24" o.c. Stick with 5/8. It will slow a car fire. It's mandatory if attached, but just good practice on any garage. Forget the strapping. It's not necessary.

 

[diggler306]

What Tdoriot said.

 

[fastjohnny]

Thanks guys.

Yeah I need to get some pics. The joist seem crazy close to me. If I were to screw into each joist there'd be a lot of nail hole spackling to do.

I've already roughed in all the wiring too. Just gotta get moving on the rest.

I hadn't decided about the fire code rock yet. I thought it was required to separate any inhabited area from a garage area. Good to hear it would be acceptable to not use it due to the structure being detached. I may do it anyway though just be be safe.

Glue......It's how it's done these days. Really minimizes need for fasteners, bonds better, less cracking, nail pops, etc.

 

[rburke65]

I would glue and screw it as said every joist...every 12". Yes, insulate and get all you wringing in beforehand. And rent that lift.....a GREAT tool!