Hello,
I have been researching how to finish the garage with drywall. The purpose is simply to make the garage look more like a "room". Our plan is to simply add drywall without even putting mud on top of it. Does this violate any code？

Attached below is a photo of some of the joists (labeled 1, 2, 3 and 4).
According to the handbook provided by USG, I need to add additional joist (2x6, about 19" span) between existing ones such that the spacing is 24" oc. 5/8" firecore sheetrock can then be attached to the bottom of the joists. Is this understanding correct?

Based on a previous thread (http://www.doityourself.com/forum/wa...+ceiling+joist), adding joist doesn't require structural engineering. Still it would be appreciated if someone could kindly point to some tutorials. I could try to mimic how the existing joists are attached to the top plate, but am afraid to miss something important.

The thread I mentioned above also talked about the necessity of removing garage door track. As shown in the photo, the track is hanged from joist #4. If I don't care about the look of the ceiling, is it ok to make a hole where necessary so that garage door can be left untouched.

Another confusing part is the appropriate nail/screw to be used. According to USG's handbook, 1 1/4" type W screw (size 6) is enough to fasten 1/2 and 5/8 drywall to wood stud. While other sources recommend 1 1/2" size 8 drywall screw. Additionally, what exactly is type W? I couldn't find any type W screw at my local store.

Finally, does this project add too much weight to the frame with the added joists and ceiling drywalls? Also, part of the side wall is already sheetrocked, which means some ceiling panel will not sit on top of these existing wall panels. Can joists carry the ceiling panel just by the screws?

Sorry for so many questions and your help would be greatly appreciated!

Oh, by the way, do I need additional vent after adding ceiling panels?

 

Interesting. Could we see more pictures before we answer? Having a 360° view of the room, plus an exterior picture of two might help us understand the framing.

Any idea when this garage was built? Also, where are you located? Codes vary based on locale.

 

Based on Chapter 8 - Roof-Ceiling Construction (link from an old thread), it seems I need to use 2x8 at least for this span if I want to add drywall ceiling. Current, I only have 2x6 without any ceiling.

Here are some more pictures.

This is the view from outside the garage door



As you enter the garage, this is the wall directly facing you. It's shared with the living room.



This is the wall on your left. It's shared with the living room.



This is the wall on your right. The other side of it is outside.




Thank you for looking into this. I am really curious if there is any "trap" in my plan.

 

Usually the code just requires taped joints where ever the wall/ceiling abuts living area BUT it's always a good idea to have input from the permit office or inspector!

What is the current ceiling joist spacing? do you intend to insulate?

 

The hickup in your plan is that your ceiling joist (which tie your load bearing walls together and prevent them from spreading) are all running the wrong direction. Give us the measurements of your garage and give us a little time for more to chime in. I don't think you should just place framing in betwren the existing.

 

XSleeper:
I guess the ceiling joists run that direction from when it was built in 1970s. If we were not going to add drywall ceiling, would it still be running the wrong direction? The garage is about 19 ft x 19 ft.

marksr
I am not planning to add insulation.

Thank you all for the valuable inputs. And here is the garage door viewed from inside.

 

Yes they definitely run the wrong direction. You can check the distance between your walls at the top plate to see if the building has spread. I would be willing to bet those walls are bowed out at the top and that the peak of the roof is sagging. Fixing all that is possible but it will require a center beam and all new ceiling joists in hangers.

 

That's sad to know. It looks like this is something to be fixed by a professional. Maybe we can forget about the drywall for now ... Thank you for providing that information.

If we look at the wall facing the garage door. It actually contains studs as other sides. It is parallel to the ridge of the roof, but not directly below it.



Is the wrong joist direction some kind of serious structural issue? Would adding drywall make it worse?

 

The ceiling joist spacing is 48 in. It's much bigger than that in the attic above living area. Is this still too big even without any drywall?

 

It is a structural issue, and yes, adding drywall would make it MUCH worse.

The solution is not a difficult one. I'm not a structural engineer, but if I was going to do it, I would first add a double 16" LVL down the middle (positioned directly below the ridge or peak of the roof, and long enough so that it can sit on the top plate of both gable end walls. LVL needs support directly underneath it within the wall.) Then you would need to ensure your other walls are parallel (the garage door wall and the one opposite) by running a string line across each wall at the top plate. If needed, you would cut loose any framing and then winch the walls together with a come-along or a few heavy-duty ratchet straps. Once that is in place, your new joists (about 9'6" long) would sit on the top plate above the garage wall (tied with hangers) and would run to the new LVL beam where they would sit in joist hangers. The spacing between the new ceiling joists should be no more than 24", but they should also be nailed to each of the existing rafters where possible... so the existing rafters may determine the layout. If the rafters are 48" apart your new joists could still be 24" on center. If they are some weird layout, like 50" apart, that kind of complicates things.