12

I too, was in search of Tuck Tape at Home Depot / Lowe's and couldn't find it. When I asked a salesman about it, they didn't understand what I was looking for. When I said I wanted to seal the edges of vapor barrier, they told me to use the Tyvek tape, the same one you found. Duct tape won't cut it; it's too porous. We used the Tyvek and it's worked well ...


8

You should NOT place a vapor barrier BEHIND the backer board. Where, pray tell, would any such collected vapor/water go? Answer:There's nowhere proper for such moisture to egress. The current best practice is to place waterproofing OVER the backetboard and just UNDER the tile. Thin sheet membranes like Kerdi or NobleFlex are examples . Paint on ...


8

I called USG,the maker of Durock cement board Next Gen, and they advised using no vapor barrier so that the wall cavity can breath and allow any moisture to evaporate. Their online instructions/diagrams show no use of a vapor barrier.


7

Yes vapor barriers are to prevent condensation inside of insulation, greatly reducing its efficiency. In your climate, if you use air conditioning and that space has insulated exterior walls, you will want a vapor barrier on the exterior side of the insulation to prevent outside humidity from condensing inside the cooler insulation. If your exterior walls ...


7

Ask yourself this: "If I install a vapor barrier, where is the water that it stops going to collect?" If you put a polyethylene vapor barrier behind a drywall-covered stud framed wall, then the answer is that water that condenses on the poly will fall onto the wood sill plate, growing mold and eventually rotting it out. Dedicated vapor barriers have no ...


6

I think you'll have to get one of these vapor barrier boxes, and fit it before installing your electrical box. Seal up where the cable penetrates, then install your electrical box. The other options would be to cut a larger hole and patch drywall, or seal it up from the back side (but that would require access to the other side of the wall/ceiling).


5

I'll answer the second question first: Where would I go looking for any such information for my location? Your city's building and code inspector's office. But note that because something is to code doesn't necessarily mean it has to be done that way--provided you can show why your way is better. Which leads to your first question: Does anyone know ...


4

Nope, it shouldn't cause problems with moisture buildup -- but how much blown in fiberglass do you have up there? If it's less than your roof joists, it's not enough, and you should think about adding some (or a lot, actually) to bring you up to R-30 at the least in your attic. If you do have that much up there, but you moved some to the side to put down ...


4

No, you only want a single vapor barrier. A second vapor barrier would create a moisture trap that would cause more mold issues. If there's a condensation issue, I'd replace the section of HVAC ducts with an insulated duct. The insulation inside the duct prevents the outside metal part of the duct from getting cold enough to result in condensation.


4

Typically, nothing is done. That puncture should be at a tight connection of drywall to stud, where airflow is impeded by the pressure of the screw holding the drywall and vapor barrier to the stud. The vapor barrier isn't an impermeable seal, it just dramatically reduces movement of air and vapor between interior space and exterior walls.


4

IMO you are making several leaps here that don't fit. You've got mold below a window, spread out about 2 feet on either side, and you suspect condensation as the culprit. You specify that the damage is old - years old by the look of it. Condensation happens every year, every season. Why would the damage be old, it should be fresh if it's condensation. ...


4

You don't seal the vents, ventilation of the crawlspace is needed to prevent moisture buildup and rot. I had to take on the very same project. There are three objectives. Under house air can have mold in it, you shouldn't be breathing it, block all air exchange between the living space and the crawl space. Under house moisture levels must be brought down ...


4

It is a good idea to seal any apertures between the crawlspace and the main house. If you have to rely on caulk and spray foam you're probably in a situation where the house has some weird structural problems - that is, you should not have giant gaps between the crawlspace and the floor above in any normal construction regimen. It is not a good idea to ...


4

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). Moist air tends to migrate toward the cold side of a wall. The vapor retarder is installed correctly, in your crawl space, to discourage exterior humidity ...


4

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.


3

Yep, the 120 year old houses do make life more interesting (and expensive and/or colder.) Use an air barrier that is NOT a vapor barrier. More commonly known as housewrap. Vapor moves through, but bulk air movement is reduced. For insulating inside the floor joists, either blown-in cellulose (which supposedly has very little issue with vapor, due to having ...


3

No, there's no need to install a vapor barrier between two conditioned spaces. The purpose of a vapor barrier is to prevent warm moist air from traveling through the insulation and condensing on the cooler side, which can easily happen in cold climates. With a conditioned space on both sides, you can allow any moisture in the air to pass through. There's ...


3

Presumably you are going to have heat early/late in the season, when it gets cold at night. If you ever want to heat the cottage in the winter, it's also significantly easier to do now than it is later. I would install a vapour barrier in this case. It's needed when warm meets cold; in cold climates, on the warm side, to prevent moisture from forming ...


3

Rigid foam insulation is usually a qualified vapor barrier. However, an installation between the studs can pose a challenge. To complete the vapor barrier you would want to foam-seal or tape all the sides where the rigid meets timber, because these gaps will facilitate vapor flow.


3

You can put a vapor/moisture barrier up over rigid foam. A lot of new construction in the far north has this as a default. The idea is that you frame right outside of that. In that framing you are allotting a cavity to which moisture can move and evaporate. Now if you are putting rockwool or other types of insulation in your framing then no you do not ...


3

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 get in past the tub surround. I would recommend paperless drywall over cement board for the tub surround, as well -- gypsum board of all types is vapor open (...


3

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 owner.


2

Just doing some repairs on my (Canadian) house and it uses black foam glue (the tube said "acoustic foam") around the edges and nails with an L shaped right angle head along the studs


2

Moist air is condensing (barring any oughtright leaks) It is most likely due to air leakage from house to attic: Ceiling to attic is leaking moist air, condensing. Solution: air sealing of all penetrations (light fixtures, ducting, electrical, gaps in construction) Insufficient insulation, combined with air leakage allows condensation to occur. Vapor ...


2

Safest bet is to replace it of course - but in your case I wouldn't call it necessary. There's an easier way to replace the vapor barrier. Run the barrier over the trusses. Keep it flush to the drywall but run it up over the truss and down again. Of course, if your house is that old that it had vermiculite, I'm going to bet that you've got about 8 ...


2

You have asked several questions at once so a little difficult to give you the answers you want. First, Hardy backer board is a newer, lighter, substitute for concrete board and usually used in bathrooms and under tile installations. I have never seen it used on exterior walls as a sheathing. Second, the huberZip system is from Advantec. I love Advantec ...


2

You should, so that any moisture that gets behind the cement board runs into the tub or shower instead of into your wall cavity (causing rot or mold/mildew). If you overlap the moisture barrier with the raised lip around the tub, any moisture has only one path to take due to gravity -- down the barrier and into the tub. I usually use thick-mil plastic ...


2

plastic behind cement board with waterproofing is essentially suspenders when you already have a belt. the waterproofing is also a vapor retarder so if the red guard or kerdi product is continuous, lapping corners and all, the plastic will be unnecessary. if you think of tile like exterior cladding, it would make sense to leave an open hole in the ...


2

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/getattachment/98adb0c7-1bd1-49e7-a9d4-a8275d29ae4a/HardieBacker-Installation-Guide-English_Spanish-HB1710.pdf Note on page 4 "vapor barrier if local codes require." ...


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