Go Back   DIY Chatroom Home Improvement Forum > DIY Repair > General DIY Discussions

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 02-03-2012, 10:11 PM   #1
Newbie
 
Join Date: Feb 2012
Posts: 3
Share |
Default

Mold on new sheetrock


10 months ago I remodeled a spare room into my daughters room. I removed the old sheetrock, insulation, and rewired. I replaced with new kraft faced insulation and then installed a 6mil plastic vapor barrier. I installed new sheetrock, painted and finished. About 2 months ago, I noticed mold starting in the corners on the sheetrock, and spreading to the base molding. I just now noticed there is another spot in the middle of the room doing the same thing. Before the remodel there was no mold on the sheetrock, but also there was no plastic vapor barrier. Im thinking the mold has something to do with installing the plastic vapor barrier??! Any ideas?

MMEL530 is offline   Reply With Quote
Old 02-03-2012, 10:25 PM   #2
Member
 
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,847
Default

Mold on new sheetrock


Your location is very important. Where r u? What else have you done to alter the situation (specifically, anything to raise the humidity, or reduce/eliminate insulation in the corners)? Has it been colder than in past winters? Does the rest of the house have a vb? What is the rest of the wall made of, outside the insulation?

jklingel is offline   Reply With Quote
Old 02-04-2012, 11:27 AM   #3
Newbie
 
Join Date: Feb 2012
Posts: 3
Default

Mold on new sheetrock


I am located in Northern New York. To best of my knowledge there is no vapor barrier in the rest of the house. It hasnt been any warmer this yr, but the temp has fluxuated quite a bit. The wall has plywood on the outside then 2" foam board and board and batten siding covering that.
MMEL530 is offline   Reply With Quote
Old 02-04-2012, 12:10 PM   #4
Member
 
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,847
Default

Mold on new sheetrock


Ah. Fairly cold. If your insulation is well done (ie, complete, detailed well, and no excessive air leakage) then I suspect you have a humidity problem. The vb should not focus any water on the inside unless it is very cold and you have the humidity there to generate condensation. Does the foam touch in the corners, or is there a gap? Are the corners lots of studs and no, or little, insulation? Obviously, the corners are cold. The questions is, Why? On the outside, it is generally a good idea to have a rain screen and weather resistant barrier between the siding and the foam. I doubt that having or not having that has anything to do w/ your present problem, though, unless you have air leakage and the accompanying water is condensing out there, thawing when it gets warm, leaking back inside, and wicking everywhere. That sounds too improbable, but that is all I can imagine.
jklingel is offline   Reply With Quote
Old 02-04-2012, 01:08 PM   #5
Retired from the grind
 
gregzoll's Avatar
 
Join Date: Dec 2006
Location: Midwest - Central Illinois
Posts: 14,026
Default

Mold on new sheetrock


Placing the plastic barrier over kraft faced insulation, is only going to cause problems. How humid is this room, along with air temp? The bad thing is, you may end up having to tear everything down and redo it, minus the plastic vapor barrier, if you are keeping the kraft faced insulation.
__________________
Ren: Now listen, Cadet. I've got a job for you. See this button? Ren: Don't touch it! It's the History Eraser button, you fool! Stimpy: So what'll happen? Ren: That's just it. We don't know. Maybe something bad, maybe something good. I guess we'll never know, 'cause you're going to guard it. You won't touch it, will you?
gregzoll is offline   Reply With Quote
The Following User Says Thank You to gregzoll For This Useful Post:
paul100 (02-05-2012)
Old 02-04-2012, 01:20 PM   #6
Member
 
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,847
Default

Mold on new sheetrock


Greg: I am no expert, but I believe the foil and poly are not of real concern, IF they are right against each other, as most folks install them. It is not good, but this came up on greenbuildingadvisor, if I recall, and the consensus was that it was "OK, but not great". I think that is how it settled out, anyway. Yes, digging in may be the only option, and doing so when it is cold. That way, one can see if/where any ice is forming in the wall. It's a can of worms to solve from afar.
jklingel is offline   Reply With Quote
Old 02-04-2012, 01:40 PM   #7
Newbie
 
Join Date: Feb 2012
Posts: 3
Default

Mold on new sheetrock


Thanks. Ive been reading up and starting to think the plastic vb is the problem. I never had this issue before, and now I do.
MMEL530 is offline   Reply With Quote
Old 02-04-2012, 01:53 PM   #8
Member
 
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,847
Default

Mold on new sheetrock


NY probably does not need a vb, but local codes vary (scientific or not, local codes are codes). If your vb is not required, I'd opt for good air sealing, in and out, and no vb. Buildingscience.com has/had maps of where vb's are generally not recommended, etc.
jklingel is offline   Reply With Quote
Old 02-06-2012, 12:00 PM   #9
Member
 
Join Date: Jan 2012
Location: Pacific North west
Posts: 1,229
Default

Mold on new sheetrock


Your problem is placing the plastic over the vapor barrier. you don't do it if the insulation already has a vapor retarder on it you just locked moisture between the sheet rock and insulation.
my question is who gave you that idea to do such a thing? Because they just cost you twice the cost and twice the labor.
Nailbags is offline   Reply With Quote
Old 02-07-2012, 04:05 PM   #10
Mold!! Let's kill it!
 
Join Date: Feb 2008
Location: Central Pennsylvania
Posts: 2,843
Default

Mold on new sheetrock


You can blame it on the plastic or the vapor barrier or whatever, but you've got moisture in the drywall on the warm side of the wall that would otherwise have penetrated into the insulation layer. In order to form moisture, the drywall and vapor barrier had to drop below dew point and/or moisture levels had to exceed 60%. Look for the cause of the excess moisture. No exhaust in bathroom? No air turnover? Room temperatures low enough to allow condensation? This is something more than a vapor barrier issue.
Maintenance 6 is offline   Reply With Quote
Old 02-08-2012, 09:28 PM   #11
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Default

Mold on new sheetrock


I agree with Maint. above. Also, you don't need an interior vapor retarder facing or the vapor barrier plastic IF the 2" foam board outside is 2# closed-cell: http://publicecodes.citation.com/ico...001_par004.htm

Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 02-09-2012, 12:10 AM   #12
DO IT RIGHT THE 1st TIME!
 
Join Date: Feb 2012
Location: NEPA - Pennsylvania
Posts: 34
Default

Mold on new sheetrock


Plastic "vapor barrier" became a vapor LOCK. You didnt need that barrier my friend, and as others have said - it just cost you more in material and labor. Plus as maint. said, its more than just the plastic. I cant add anything to what he said.
builttolast is offline   Reply With Quote
Old 02-09-2012, 01:11 AM   #13
Newbie
 
Join Date: Feb 2012
Posts: 3
Default

Mold on new sheetrock


NY probably does not need a vb





______________________________
enjoy game so much!
wow gold Buy Maplestory Mesos wow gold

zhuzhuxiao is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
How to - prevent basement mold crazymountain How To Guides 36 07-23-2014 06:02 PM
Mold found - unsure what to do?? izzyant88 General DIY Discussions 12 06-17-2011 06:21 AM
Mounting a flatscreen TV on a sheetrock wall TanMan Building & Construction 14 02-16-2009 04:26 PM
Concrobium or White Vinegar? eis61374 Remodeling 8 11-17-2008 06:56 AM
mold resistance sheetrock drywall worth it stefjeano Drywall & Plaster 1 11-03-2008 06:57 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.