Do you put Vapour barrier on interior walls?
The IRC recommends builders install a Class-I or -II vapour retarder on the interior side of homes in climate zones 5 (Cold) and north, and in the Marine 4 zone. However, if you air-condition your house in the summer, your might trap condensation in your roof or walls for part of the year.
Can you vapor barrier over drywall?
Interior Walls Interior bathroom and kitchen walls, for example, are areas where there is great benefit to installing a vapor barrier. The paint acts as a vapor barrier as well. A continuous plastic vapor barrier behind the drywall will protect the interior walls of these areas from water damage.
Is a vapor barrier necessary behind cement board?
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.
Do you need a vapor barrier behind drywall?
No, you don’t need a vapor retarder, Class I or otherwise. By the time you paint the drywall, though, you’ve brought it into the Class III vapor retarder range (between 1 and 10 perms), and even less water vapor will diffuse through. Seal the air leakage pathways.
What side of insulation does vapor barrier go?
Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets. This barrier is meant to keep moisture from getting to the insulation in the walls and ceilings, and it is required by building codes when insulating most houses. In any case, the vapor barrier must point to the warm side.
Do you put plastic behind cement board?
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.
Is painted drywall a vapor barrier?
Class III vapor retarders are identified by the IRC as latex or enamel paint. However, research shows that standard painted drywall is commonly vapor permeable (greater than 10 perms, up to 40 perms) – a benefit during the cooling season, but a potential concern during the heating season.
Should I use a vapor barrier in basement?
Building codes usually require a vapor barrier (4 mil plastic sheeting) on exterior basement walls if the framing is attached to masonry or concrete surfaces, or if the wood framing butts up against the outer basement walls. You should then use fiberglass insulation that has a vapor barrier between the studs, with the vapor barrier facing in toward the living space.
Where to install a vapor barrier in a bathroom?
Where you should put the vapor barrier in your bathroom depends mostly on the climate in the area where you are. If you live in a hot and humid location, the vapor barrier must be installed on the outside wall. If you live in a colder climate, you must install your vapor barrier on the inside of the wall.
What is a vapor barrier in a basement?
A basement vapor or moisture barrier is installed during the new construction of a home or the remodeling of a basement. Polyurethane sheeting is a typical vapor barrier that contractors use to prevent moisture from penetrating the walls of a basement. The material is stapled to the frame of a basement wall before it is finished…
What is the thickness of a vapor barrier?
Vapor barrier thicknesses range from 6 mil to 20 mil, with 6 mil being the bare minimum and 20 mil being the most heavy duty and puncture-resistant.