perry 82 #1 Posted December 12, 2008 just picked up 26 sheets of drywall for $80 . 1/2" 4x12 i plan on starting with the ceiling in the shop/garage tomarrow. i put plastic on the ceiling a few years back to help hold the heat in. my question is, should i tear down the plastic or just cover it up with the drywall ?. will it create a moisture promblem if i leave it ?. Share this post Link to post Share on other sites
WH854 44 #2 Posted December 12, 2008 My house is plastered! when they put the insulation in they put aclear plastic over the insulation.Then nailed backing board over the plastic, then put base coat of plaster over that, then a finish coat of plaster. Never had any problems They heat a house in the winter when they plaster If they are vinted right you shouldn't have a problem. thats my 2cent Chas. :hide: Share this post Link to post Share on other sites
Duff 206 #3 Posted December 12, 2008 I would think the plastic would act the same as the vapor barrier on foill and kraft faced insulation which always faces toward the inside or heated part of a structure, so IMHO it shouldn't be a problem to leave it there and actually may help things out. We have some professional builders among our members - your thoughts, guys? Duff :hide: Share this post Link to post Share on other sites
kj4kicks 151 #4 Posted December 12, 2008 Hi Perry, You should take the plastic down. If for no other reason, drywall should be glued (construction adhesive) and screwed (NOT nailed) to the framework above. Also, if the ceiling is on 24" centers, you should really use 5/8" drywall there, so it doesn't sag with time. If they are 16" centers, you might get away with the 1/2" , but I wouldn't. ALWAYS install the ceiling first. That way the wall boards help support the edges of the ceiling boards. Share this post Link to post Share on other sites
stevebo-(Moderator) 8,040 #5 Posted December 12, 2008 I am in the mod bit roofing industy and it is always good to spec out a vapor barrier. I would say leave it in place and I agree that you will need to screw it not nail it. I am not a builder however I have not seen any sheetrock hangers use the structrual adhesive however if you do then I agree you will need to take it down. Good luck... Share this post Link to post Share on other sites
charger10us 1 #6 Posted December 12, 2008 I'm finishing up a bedroom now in an older house, that has plastic agaist the dry-wall. IT WAS NOT GOOD. the plastic held mosture & milldewed the dry-wall & rotted out some of the wall studs. There is a big differance in wraping the house, then insulation then dry-wall, that's good! Myself, the plastic would come down!!! Share this post Link to post Share on other sites
kj4kicks 151 #7 Posted December 12, 2008 Faced isulation will provide the vapor barrier, and still be "breathable" . Guess I should have been more clear about that. Glue is cheap, about 3 or 4 bucks for the big tubes. Why take the chance of it failing (and falling) ? Share this post Link to post Share on other sites
linen beige 14 #8 Posted December 12, 2008 In most parts of the country a vapor barrier is not called for in horizontal installations such as above a ceiling. Some local codes even forbid it. That includes Kraft faced insulation. Vapor barriers of the complete and total contact type such a foil faced paneling, or rigid foam insulation with foil barriers are usually allowed since they don't have gaps that can trap condensation. Use the glue and screws. When applying the glue run a 3/8 to 1/2 bead straight down the center of the joist edge. Joist (and stud) edges are seldom as flat as the drywall surface. The glue bead will fill any gaps as you screw on the drywall. If you put a screw through where the joist doesn't quiet contact the drywall and don't get the sheet quiet snug against the joist the glue will fill the gap and keep the screw head from pushing out against the mud when the joist expands or contracts from temperature/humidity changes as the seasons change. Had I known this when I "saved a few bucks" building onto my house I wouldn't need to go back and redrive some screws after it's painted. Using the glue also lets you use fewer screws. That's a big help when you're driving them over head. Share this post Link to post Share on other sites
Pacific Dog 1 #9 Posted December 12, 2008 Remove the plastic! The drywall needs to breathe in order to prevent mildew and mold from growing due to moisture from leaks or high humidity. Moisture barriers should be on the outside portion of a wall/roof unless in certain environments (low humidity deserts). Insulation materials that can be placed directly against drywall are designed to let vapors and moisture to pass through. Share this post Link to post Share on other sites
COMB2 0 #10 Posted December 12, 2008 I would take the plastic down also. I'm in new house just about everyday and I have never seen anyone use glue. IF it's done correct you will never have the screw head problem. I've done my own Drywall before, it's a pain in hte butt and also not perfect. I know your tring to save money but see if you can find a guy to do it on the side. Cost like $200-$400 and he will have it done in like a day or 2 and it will look good. Or hang it and tape it and use a popcorn gun on it. Thats what I did in my garage. $60 for a gun Share this post Link to post Share on other sites
refracman 166 #11 Posted December 12, 2008 Perry, If your not going to heat this area you can use drywall but do not tape it. The drywall will shrink and the joints will seperate and the tape/mud will crack. You would be better off to use 1/2 osb and caulk the seams. It is code in Ohio and I believe Mi. that 5/8s is used in all overhead applications no matter the joist / rafter spaceing and two layers in all walls and attic areas adjoining living areas. Never use poly in a ceiling app. as like stated before moisture will be traped between the drywall and poly and mold / rot will occur. You can use poly in wall apps only when useing nonfaced insulation. It is up for debate in the wall apps still if you have house wrap on the exterior, some believe that if both are used this will cause a moisture trap. The screw / nail issue is debateable. Used both and seen both. If nailed correctly they hold just as good. Nails are by far cheaper but screws are a lot easier if you have a screw gun / drywall bit. I allways space every 8 inches in the field and 6 on the seams in the ceiling no matter which fastener. And where did you get your drywall ? thats a good price! Share this post Link to post Share on other sites
perry 82 #12 Posted December 13, 2008 the ceiling is done . and i did take the plastic down. me and my buddy started at 9am this morning and done by 8pm. with a garage that is pretty darn full of shelfs and stuff. the 4x12 sheet rock say's ceiling board anti-sagging on the stickers. i bought it last night off craigslist. wound up getting 28 sheets for $80. had to hual it out of a basement ...uugh! . then after hanging it today im beat. i am not use to all the stairs and ladder work . atleast it was clean and dry. the guy even had some nifty drywall carriers. i was surprised the 12 ft'ers went up pretty easy with just the 2 of us. my buddy is the carpenter not me. after he made his measurements and cuts we started screws threw out the board before we raised it up. we just flung it up to the ceiling, got it set and screwed it down. that was nice haveing the middle screws all pre-measured and pre-started. i never even thought of doing that. now tomarow i have to get my garage back in order. i have a heater core to do in the wifes caravan and possibly swapping the engine in my pick-up . figures both our cars puke out at christmas time. . . the heater core is going to be a MAJOR job. have to pull the dash out of the van. but atleast i have a back engine for my pick-up i needed, and that a easy one day job . Share this post Link to post Share on other sites
perry 82 #13 Posted December 13, 2008 oh ya. we start my buddys ceiling on monday. that was the deal. i bought the drywall he hangs it. with my help ofcourse. heck i could'nt beat the price. and his garage is only a year old with less stuff in it and a touch smaller. my garage is a 24x24.. Share this post Link to post Share on other sites
HorseFixer 2,012 #14 Posted December 14, 2008 Show us some picks! Glad ya got it done perry! :hide: Share this post Link to post Share on other sites