Can you put a vapor barrier over faced insulation?

No, you should not do this. As mentioned above, faced insulation that has a vapor barrier can easily trap moisture. If you put another faced insulation on top of face insulation, a significant amount of moisture can form inside your insulation and in your walls to damage them.

Do you need a plastic vapor barrier with faced insulation?





Fiberglass Insulation



In most climates, it needs a vapor barrier. Some builders rely on batts with attached kraft-paper facing to do that job, but Tom recommends unfaced batts, covered in plastic with all the seams taped shut.

Can insulation be put in upside down?

Insulation in attics and crawl spaces is often installed backwards. Not many people know that that pink panther home/wall insulation can actually be installed upside down, but it can. Insulation should have its paper side installed towards the inside of the home.

Which way should vapor barrier face?

Picking the right face is essential with fiberglass insulation that has a vapor barrier (meaning with Kraft paper or foil attached on one side).

  1. It should always face the warm-in-winter side. …
  2. If a vapor barrier is installed on the wrong side, it can trap moisture inside wall cavities causing condensation to accumulate.

Can I put Poly over faced insulation?

More than likely, installing an additional layer of poly over kraft facing won’t cause any problems — it’s no more risky than if the wall had only unfaced batts and poly — and the risk of using poly on the interior is relatively low in a cold climate like New York’s.

Is it OK to put plastic over insulation?





Install the plastic sheeting only after the insulation, wiring and plumbing have been completed. Stretch the plastic sheet tightly across the top of the wall and staple it to the studs and plates with a hammer-tacker, a tool designed to install staples quickly and efficiently.

Should I put plastic over insulation before 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.

What kind of plastic do you use for a vapor barrier?

Reinforced polyethylene plastic sheeting

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.

Can you put plastic over insulation in attic?



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.

Which way does the vapor barrier go on insulation?

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.

Which way should insulation face in crawl space?

Whether it’s in a basement, a crawl space, or an attic, the insulation should face the unconditioned side of the house, while the paper faces the conditioned side. Insulation gets installed in this manner to prevent moisture and water damage from occurring.

How do you install insulation in vapor barrier?



Quote from the video:
Quote from Youtube video: We're just trying to get as much r-value as we can when installing insulation you want a fairly snug fit. But you don't want to have to pack it in there and get it compacted as soon as you compact.

Can you use 4 mil plastic for vapor barrier?

OVERVIEW. Our 4-mil plastic sheeting is a multipurpose film perfect for a wide variety of construction or DIY projects. This medium-duty plastic sheeting is commonly used as a vapor barrier in between insulation and drywall, used as a drop cloth or a temporary cover for equipment and supplies.

Can you use plastic sheeting as a vapor barrier?

In simple terms, a vapor barrier is a material that won’t allow moisture to pass through it, such as plastic sheeting. A very simple experiment to show how a vapor barrier works is to lay a plastic garbage bag down on some damp soil.

How do you secure a vapor barrier in a crawl space?

Experts say the plastic should be secured at a distance of about six inches up the wall. Next, use the landscape fabric stakes to keep it protected for potential future disturbances. Chances are that someone will have to slide around in the crawlspace later to fix a pipe or run a new cable.

Should I put plastic in my crawl space?



Homeowners use plastic to cover their crawl spaces to control moisture and create a barrier against vapor. Without such a barrier, condensation can infiltrate your home’s walls and insulation, creating a substantial risk of mold and mildew. Plastic sheeting can also help turn a crawl space into a usable storage area.

Should I put a vapor barrier in my crawl space?

Yes. You need a vapor barrier in your crawl space. What’s more, a moisture barrier is the minimum amount of protection that you should have in your crawl space. A vapor barrier helps you to avoid expensive repairs.

Is 6 mil plastic good for crawl space?

For starters, 6 mil is too thin. Durability is going to be a major concern in a crawl space. If a home is built with a crawl space foundation, it is likely to have HVAC duct work, plumbing, electrical, and other cable wires running through it. This makes for a high-traffic area for a variety of contractors.

How long does 6ml plastic last?

6 mil plastic could survive the sun for up to 3 years. Fifty eight years later 6 mil poly is still used by the budget conscious grower. This film will get you by. The downside to 6 mil is bad weather (wind, snow load, hail), and strong sun.

How thick should a vapor barrier be in a crawl space?



Vapor barriers should be at least 6 mil in thickness to effectively cover the area and create a moisture barrier. Triangle Crawl Space Solutions uses both a 6 mil material for simple vapor barrier installation and a thicker more durable 12 mil vapor barrier material depending on the budget and needs of the home.