Details about drywall under tongue and groove as an air barrier
mattseab
| Posted in GBA Pro Help on
I have read often on gba about the importance of using an air barrier under tongue and groove and I may be over thinking it but it seems that 1/2″ ultralight has the potential for more air leaks around nail penetrations due to occasional voids in ultralight and that 1/2″ could more likely bust around nail penetrations and let air in versus 5/8″ but before I wear myself out hanging 77 lb sheets I figured I should ask an expert.
Thanks,
Matt
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Replies
Matthew,
I would go with the 1/2-inch drywall, but I'm basing my answer on instinct. I have never heard of any relevant testing that might answer your question.
I was thinking about caulking on top of the drywall over studs just before I nail the t&g in order to seal and potential openings in the sheetrock. Do you think that is overkill? I'm asking because I have gone to great lengths to seal up the house and have been adhering to the airtight drywall approach on areas that will not be covered with t&g so I was just trying to make sure the integrity of my air barrier stays good.
Matthew,
I did like you did - went to great lengths to seal up a house we built. I mean I spent hours and hours with tape and caulk and special sealants. I sealed every rafter bay, stud bay, nails through the sheathing, everything. But the things that are going to really going to count are around the doors, particularly at the bottom, penetrations made by plumbers, electricians, HVAC guys, dryer and vent ducts. And those were things I could hardly get to once they were done. The dryer vent really frustrates me to this day.
My point is that this is overkill - get the ducts and vents and doors (at the bottom, especially) right and you've got the house the way you want it.