Sorry – I’m “double posting” this from “construction techniques” into this discussion gallery as well – if I can’t delete the previous posting.
I went with a friend to a rent house he owns to help him determine what repairs and improvements might be needed. The tenant is moving after 15 years occupancy. Along with upgrades, the interior needs a good deal of repair, cosmetic and major.
The house was built in the lates 60’s and has a slab foundation with sleepers. The living room ceiling is sheetrock, probably 1/2″, and has numerous cracks running lengthwise and endwise along the joints. He recalled that during his ownership, the ceiling has been retaped and mudded several times, but that the cracks have kept reappearing over the years. At this point, the ceiling needs replacement.
I am wondering if a solution might be in glueing and screwing plywood to the ceiling joists (not trusses) and installing new sheetrock over the plywood “sub ceiling”.
If that sounds like a plausible solution, would it be better to run the sheetrock perpendicular to the plywood? And, would separation cracks be likely to appear where the ceiling and walls join? If that sounds likely, would crown moulding help disguise that movement?
Any thoughts about this idea, or another solution, are appreciated.
Replies
I would really try to determine what causing the cracking
Joseph,
I think determining the cause of the cracking is certainly in order. You mention that this is stick framed. Do you know if those joists are correctly sized for the spans and loads that they're carrying? If there is a floor above it, did the renter put a waterbed up in the bedroom there? Otherwise, is there some excessive settling going on - is the slab cracking as well?
In any case, adding plywood skins to the bottom would add significant load to those joists which they're, in all likelyhood, not really rated to carry. Besides, adding plywood would probably just move the crack locations to the joints between the plywood sheets, although using T&G would help, but thin plywood (under 1/2") I believe isn't available in T&G. (I could be wrong, I've just never seen it).
If you do find that the joists are properly sized and settling isn't the issue, the easiest way to solve this is to apply strapping (1x2's) perpendicular on the bottom to the run of the joists and then fasten your sheetrock to that strapping. The 1x2's provide a bit more flexing and give, not too much though, allowing the sheetrock and the joints to remain intact.
Still, without knowing what's going on in this structure, you could easily be fighting a losing battle.
--
Jay
I would suspect that adding plywood would strengthen and stiffen the ceiling. (Not that I'm an advocate of the plywood solution.)
Something is moving...either from seasonal changes or, like Jay says, dynamic load.
Gotta figure out what is causing it.
Here's what I have learned about fixing hairline ceiling cracks. And it works for me.
Grind down all the mud with cracks in it to the drywall and remove all paper tape.. Then take a knife and get all the compound out of the grouve or space between the drywall. Dust yourself off and take the rest of the day off.
On any butt seams, make a small V groove to hold compound. Now, using 45 min Durabond, fill all gaps between drywall sheets. This should be made as smooth as possible because no sanding will be possible. By filling the gap, I mean just the gap, not the tapered edge. You will need the tapered edge to set the new paper in. Basically, you are adding the Durabond to make one continous sheet of drywall over the ceiling. This stuff drys rock hard and will not move.
When the Durabond is dry, you can use paper tape and Green compound or I prefer to use fiberglass tape and 45 minute Easy Sand. Fill to finished level.
After this is dry, Use mud from the Blue bucket for one more coat. Then sand.
Marv
Whenever I use mesh tape I first coat it with Durabond. For the same reason you mention prefill-dries harder, has more adhesive than bucket mud and because that's the way I was taught. Most any topping after-I use bucket mud sparingly anymore-usually for a final skim. I hate to wait.
plywood ceiling is overboard
What your friend has is perfectly natural cracks from houses moving and settling. Just like the other guys said, the old seam tape should be removed, then re taped with mesh tape, plastered, sanded, primed, painted.. done.
There may be other things going on but it sounds like a simple case of the house settling in. Good luck!