5
votes
Should I put vapor barrier only on exterior wall of a bathroom?
The TL;DR -- vapor barriers belong on the outside only
You should only place a vapor barrier on the exterior side of the exterior wall, allowing the assembly to dry back to the inside if water does ...
- 81.7k
4
votes
How to deal with upside-down insulation?
Nearly all of Virginia is considered to be in the "mixed-humid" zone. On an annual average, moisture migration is fairly evenly distributed (alternating toward the interior and toward the exterior). ...
- 1,346
4
votes
Can the vapor barrier between a dry floating concrete slab and linoleum flooring be foregone?
Insulated slabs usually have vapor barrier underneath. Since you did a test and found no moisture, there should be no problem installing vinyl flooring on it.
- 129k
4
votes
Accepted
Fixing a drywall hole near shower
Looks like an old-school shower area install with roofing felt (not plastic, at least looking at the pictures.)
"Rubbery and a little paper-like" - felt soaked in tar. Probably still smells ...
- 201k
3
votes
Install plastic between drywall ceilings and rafters?
the plastic will trap moisture in your sheetrock and can cause black mold
some areas require hazmat teams for black mold removal, Ran into this a few years ago and it was quite expensive for the home ...
- 102k
3
votes
Cost effective insulation for a 100 year old home?
I'd go with rock wool batt insulation in the stud bays.
Rock wool has several advantages over fiberglass. Better sound deadening ability. Better fire resistance. R-value unaffected by moisture. ...
- 13.4k
3
votes
Accepted
A creative Eco-friendly Underlayment for a metal roof?
Red Rosin Paper (which is a bit old-school, but can still be found) would fill the bill, I believe. It's plant based. Seems to be getting sold for floors now, but was the thing people used before ...
- 201k
3
votes
Can I use a ground trench as a concrete foundation form?
You can purchase "insulating concrete forms" made of foam that are designed and reinforced to withstand concrete pressure (if not damaged while being installed - there are some horror ...
- 201k
3
votes
How do I install a vapor barrier on the exterior of an existing wall?
Vapor barriers belong on the warm side of the house. The answer stating that vapor barriers belong on the outside only because air conditioners is assuming that everyone lives in a warm climate and ...
- 775
3
votes
Would unfaced insulation with a plastic vapor barrier work better than faced insulation in a finished attic?
Poly sheeting provides an unbroken vapor barrier which can be sealed to adjacent sheets, framing, etc. using proper caulk sealant. Faced insulation leaves less effective joints between every cavity. ...
- 129k
3
votes
Accepted
How do I vapor seal around a fireplace exhaust?
If (as I'd expect) the concentric stovepipe is rated "zero clearance to combustibles" you can seal right to it. The exhaust is in the inner pipe, and the outer pipe is cooled by the air ...
- 201k
2
votes
What are the pros and cons of adding a vapor barrier behind shower backer board?
Follow manufacturer's instructions first and foremost. Also in places with hot humid climate vapor barrier on the inside wall causes more trouble than it fixes.
https://www.jameshardiepros.com/...
2
votes
Accepted
Vapor barrier problems
Ideally, you would have used rigid insulation against the concrete. This would have worked as both your insulation and a vapor retarder (but not barrier). These days, vapor barriers are frowned upon ...
- 24.2k
2
votes
Accepted
Should I add a vapor retarder to an interior cinderblock wall as part of my basement remodel?
Are you sure it was mold? It may have been mildew. In my experience, mildew can grow on nearly any surface as long as it stays moist...be it bare concrete or painted concrete.
In this case, the ...
- 24.2k
2
votes
Vapor Barrier for Wine Cellar
Closed-cell foam insulation is a vapor barrier itself. If this closed-cell foam is continuous, then you shouldn't have any issues. If it is just in the cavities between wood studs, then the studs may ...
- 1,072
2
votes
How to deal with upside-down insulation?
Kraft paper is a vapor barrier (or more accurately a retarder), and in my opinion it's no more a fire hazard than the lumber it's stapled to and all the stuff you have in your home. Inspectors ...
- 129k
2
votes
How should I mend the plastic sheeting behind my drywall?
The standard now is to never do that again especially if you use air conditioning. Building science has determined this was a very bad idea because it traps moisture within the wall cavity. Here's a ...
- 185
2
votes
Proper way to install subfloor in kitchen
We use to specify building paper between the underlayment and subfloor. About 10-15 years ago we stopped. Now, we worry about moisture (vapor) getting trapped between the underlayment and subfloor.
...
- 23.1k
2
votes
Insulating existing basement wall
Much depends on the dryness of your basement. For most basements, worthy of being made into finished living space, 3 mil. plastic sheeting between the framing and basement wall should be sufficient ...
- 1,346
2
votes
Accepted
How good of a vapor barrier is OSB in a dirt crawlspace?
Moisture barriers are not a water tight seal kind of thing.
If you cover 75% of the dirt then you should reduce the mustiness by about that much.
Anything will probably be an improvement and if is ...
- 19.8k
2
votes
Accepted
Is it necessary to replace plastic covering pink insulation in bedroom exterior wall?
You are fine. Vapor barrier holes of that size and bigger are typical in wall construction, in the form of switches, outlets, plumbing, etc.
Let's keep calling it a vapor barrier. Makes geeky ...
- 2,006
2
votes
Should I use a vapor retarder in Missouri?
The US Dept of Energy also says 1/16" back drainage cavity for siding is appropriate even though capillary action occurs up to 1/4". Point being, the department of energy tends to lag significantly ...
- 31
2
votes
Accepted
How should I repair small tears in the kraft paper insulation caused while running a new water line?
You're right that your bathroom will have a lot of moisture in it, but if that much gets through to your insulation you're not ventilating enough. Make sure you run your bath fan regularly and for ...
- 129k
2
votes
Accepted
Vapor barrier behind electrical panel?
Since the garage is not within the conditioned envelope, then no
The key to understanding a "vapor barrier" (really, an air barrier) is to understand that it is part of the system that separates "...
- 81.7k
2
votes
Densheild tile backer board use advise needed
I use Denshield on every shower i do.
I understand the manufacturers recommendations but i think it is good practice to go the extra mile and use a waterproofing membrane on all seams and screw ...
- 13.5k
2
votes
Accepted
How to insulate metal roof on shed and avoid condensation?
You need to prevent air from getting to the metal. If no air circulation there is no moisture will condense on the inside. Spray on insulation works well but is fairly expensive, Fiberglas works but ...
- 102k
2
votes
Should I put a moisture barrier between a single ply of pressure treated (PT) plywood and a second non-PT ply when constructing a shed?
Dont put moisture barrier between, it will just trap moisture and rot quicker. Moisture for shed should be under structure. But if it collects rain water on top you are just making humidity worse. Pt ...
- 371
2
votes
Cost effective insulation for a 100 year old home?
Vapor barrier goes on the WARM side of the insulation. So plastic up against the boards and insulation on top is a bad idea.
If you've got the walls down to studs and sheathing, furring out the studs ...
- 201k
2
votes
Accepted
Do I need a vapor control membrane inside the roof if I have a breathable underlay outside?
Vapor barrier against the inside of the building envelope is to prevent interior moisture, caused by normal human activity, from condensing at the dew point. That usually occurs somewhere in the ...
- 129k
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