behind the green board
#1
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behind the green board
I am installing a bathtub wall kit. There was tile a couple of feet around the tub, so I removed it. The shower valve is new and I am ready to renew the drywall. I believe green board is a good choice. I thought about cement board, but will the walls sucessfully attach to the cement. Anyway, decided on green board. I intent to insulate the walls (no insulation at this time) This brings me to my question. Would it be good to put up some tar paper on the studs before the green board so that in the event the wall kit leaks it won't rot out the studs as fast. I have read that this is a bad idea because it will trap the moisture in the walls if it gets past the green board.
Any thoughts,
J
Any thoughts,
J
#3
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What kind of tubwall kit??? Greenboard is usually OK for tubwall kits(plastic, solid surface, etc) that cover what would usually be covered with tile. Greenboard is not OK under tile. As for a moisture barrier, not necessary, but not a bad idea if you have it down to the studs. I would use 4-6mil plastic, however. And insulate outside walls.
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Greenboard requires the use of unfaced insulation whether an exterior wall or when used in interior walls as sound dampening. While not needed, you could use roofing felt. It would be a moisture barrier but unlike the poly sheeting, it's perm rating is much higher and therefor is not a vapor barrier.
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unfaced
Greenboard requires the use of unfaced insulation whether an exterior wall or when used in interior walls as sound dampening. While not needed, you could use roofing felt. It would be a moisture barrier but unlike the poly sheeting, it's perm rating is much higher and therefor is not a vapor barrier.
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All the insulation I saw at the store was faced. I was planning to use John Manville confort-thermo with acrylic binder. I think it has a vapor retarder-MR faced mat. Should I remove it from the binder? (The plastic its wrapped around) Is unfaced insulation regular insulation without any barrier? What the difference between moisture and vapor barriers. This wal I am insulating is an outside wall with stucco siding. In California.
If I am understanding you right the unfaced installation then the foofing felt then the greenboard.
Thanks,
J
If I am understanding you right the unfaced installation then the foofing felt then the greenboard.
Thanks,
J
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Tub wall kit will be plastic. The insulation issue seems to be debatable. I have it down to studs. I don't understand if faced insulation has a barrier. What type of barrier? If it's a moisture barrier then faced insulation would work? It would give me insulation and a barrier.
Thanks,
J
Thanks,
J
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Still confused about greenboard
Just still unclear on the insulation type to use behind greenboard. If Greenboard has a perm rating of <1 then it is a vapor retarder ( vapor barrier). I believe greenboard has a rating of 30.2 so does this not make it a vapor barrier and if this is so then the insulation behind it needs to have a vapor barrier. The stack up from the outside in are stucco, tar paper,insulation, kraft paper, and then greenboard in the inside. The craft paper will be the vapor barrier with a perm of 0.40 and the greenboard with a perm of 30.1 will not trap the vapors causing moisture to be trapped between the two. If this sounds correct please advise. Maybe I am not getting my info right.
Thanks,
J
Thanks,
J
#9
I'd suggest to post your insulation question in a new thread at the insulation-radiant-vapor-barriers Forum
Insulation, Radiant and Vapor Barriers - DoItYourself.com Community Forums
Insulation, Radiant and Vapor Barriers - DoItYourself.com Community Forums