If the basement is finished and has no moisture issues, the vapor barrier is not needed. If it has moisture issues, the vapor barrier is probably a problem.
Do you need a Vapour barrier in the basement?
When you might need a vapor barrier in your basement
Your heating bills are higher than they should be. There’s visible mold or mildew in your basement. Your basement smells musty. There’s visible moisture seepage.
Should I put a vapor barrier on my ceiling?
In hot-dry climates a vapor retarder should also not be installed, but attics can be vented. All attics — vented or unvented — should have an air barrier (a properly detailed airtight drywall ceiling, for example) regardless of climate.
Will a Vapour barrier stop condensation?
The vapour barrier prevents the warm air or water vapour from penetrating through the wall to where it might reach its dew point. This, in turn, lowers your risk of internalised condensation and damp damage. A vapour barrier can be used for: Timber frame constructions.
Will a vapor barrier reduce humidity?
A vapor barrier blocking evaporation of ground moisture will lower the relative humidity in the crawl space and hopefully the mustiness you complain of.
Should I put plastic behind drywall in a basement?
Basement wall systems should never include any polyethylene. You don’t want poly between the concrete and the insulation; nor do you want poly between gypsum drywall and the insulation. You don’t want poly anywhere.
Where should I put the vapor barrier in my basement?
Not to be confused with a vapor barrier—which is placed on the warm side of the wall just in front of the insulation and behind the drywall— a moisture barrier goes against the basement wall and behind the insulation and framing. The best option for insulating a basement is to use spray foam insulation.
Should you put plastic between insulation and drywall?
Without poly beneath the drywall, water vapor hits the drywall and diffuses through to the drier (in summer) indoor air. By installing a sheet of poly there, you cut off that drying mechanism and water that finds its way into walls can stay there longer and do more damage.
How do you install a plastic vapor barrier on a ceiling?
Quote from the video:
Quote from Youtube video: The first step of installation is carrying a roll to the room. And then rolling it out then cuts the sheet with scissors.
Does drywall act as a vapor barrier?
The permeance of unpainted drywall is very high, generally between 20 and 90, so it’s not a vapor retarder at all. Meanwhile, air leakage through a 1 square inch hole in a sheet of drywall allows 30 quarts of water vapor to pass through the drywall under the same conditions. A third of a quart versus 30 quarts.
Do vapor barriers cause mold?
The Problem With Vapor Barriers
This can lead to significant moisture problems and mold; problems occur when walls get wet during construction or more often throughout the home’s life.
Do you need a dehumidifier with a vapor barrier?
Quote from the video:
Quote from Youtube video: It because chances are there's a gap here a slice there whatever it may not be attached properly to the wall. So some can get from up behind the wall. So dehumidifier would be my recommendation.
Can I use plastic sheeting as a vapor barrier?
Reinforced polyethylene plastic sheeting (poly) comes in a variety of thicknesses and strengths. A 6 mil thick poly is commonly used as a vapor barrier and offers short-term savings to the homeowner.
Should you put plastic on basement walls?
Should I use Visqueen or plastic sheeting on the framed basement walls? No, you should not, as plastic will prevent moisture from moving through the wall and will lead to mold and damage.
Is it OK to cover insulation with plastic?
Plastic isn’t recommended in this situation because it would create a second vapor barrier that can trap moisture and result in condensation and mold. Craft paper would have the same problem, this is what is most likely on the other side of the insulation for the vapor barrier you want.
Can I use plastic instead of Tyvek?
You can use plastic if you put polyethylene between your drywall and the wall studs. This way, you should get a tighter wall without trapping moisture inside the exterior walls. If you are framing out a below-grade basement, however, do not use plastic as a vapor barrier.
What can you use instead of Tyvek?
Alternatives to Tyvek
- R-Wrap.
- Tar Paper.
- StrongSeal.
- Zip System.
- Foil Insulation.
- Insulated Concrete Form.
Can you use house wrap as a vapor barrier?
For example, House wrap by itself is not an air barrier, it is a vapor barrier. However, IF installed properly, which is rare, with taped seams, bottom, top edges, and no tears, it acts as an air barrier. So primarily it acts as a vapor barrier, but installed properly can do both; vapor barrier and air barrier.
What is the difference between a moisture barrier and a vapor barrier?
Moisture barriers function to help in preventing water from entering inside of the wall cavity. On the other hand, vapor barriers basically prevent water vapor from the interior of the house to filter through the wall and condense on the warm side of the insulation.
When did vapor barriers become code?
Since 1948, building practices have changed
Although building code requirements for vapor barriers were totally unjustified when they were first established in 1948, there have been three technical developments since then that have changed the way interior vapor retarders affect wall performance.
