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.
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Should I put plastic over insulation?

Without a vapor barrier in place, condensation inside the walls could ruin the insulation and promote the growth of harmful mold and bacteria. Plastic, specifically 6-mil polyethylene plastic, is the most commonly used vapor barrier.
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What do you cover insulation with?

After the insulation is installed, it is necessary to cover it up with a vapor barrier so the glass fibers are not inhaled. The best vapor barrier to use is roll of plastic sheeting. This vapor barrier is easy to install and does an excellent job.
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Can I cover fiberglass insulation with plastic?

Fiberglass insulation will not degrade unless exposed to water. The fiber could become airborne if a vent is blowing on it or it is disturbed in some way. It can be covered with a plastic vapor barrier to protect your home air quality.
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Can I put plastic sheeting 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.
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Plastic Over Your Windows--How Much Can You Save...Really??



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.
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Do vapor barriers cause mold?

One of the more common problems with crawl spaces that do not have a crawl space vapor barrier system is that they create high moisture levels, which may result in mold growth – as dampness creates the ideal environment for mold growth.
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Is it safe to leave insulation uncovered?

"Fiberglass insulation should never be left exposed in an occupied area, according to the American Lung Association," says ALA's Godfrey. "Exposed fiberglass insulation, once in the air, does cause respiratory reactions, such as dry, scratchy throat and coughing, as well as acting as a skin and eye irritant.
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Should exposed fiberglass insulation be covered?

In this case, even if you don't plan on completely finishing the basement, you should cover the exposed fiberglass insulation for safety reasons, including disturbing fiberglass insulation can send particles into the air that act as lung, eye, and skin irritants and children playing around exposed fiberglass insulation ...
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Can I cover fiberglass insulation?

Covering Exposed Fiberglass Insulation

Common solutions for covering exposed insulation include: Sealing the insulation by stapling a polymembrane sheet over it. Installing paneling or sheetrock over wall insulation. Installing plywood flooring over floor insulation.
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What insulation can be left exposed?

What Type Of Insulation Can Be Left Exposed?
  • It has been installed so that the paper facing is placed against the inside of the wall (against the sheetrock or other building material). ...
  • It has no paper facing at all.
  • Fiberglass can be left exposed if it has a special flame-resistant foil facing.
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Do you 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.
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Does insulation need to breathe?

The insulation needs to “breathe” to do its job, so there must be a flow of air to the outside surfaces of the insulation. Paradoxically, insulation also needs to be sealed off on the inside surfaces. Walls or ceilings must be lined with a vapor barrier, a layer of a watertight material.
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Do you need a vapor barrier over insulation?

Because it is mostly hot and very humid outside the building, the vapor barrier should be installed on the exterior of the insulation. This is recommended to keep the outside moisture from getting into the less humid, cooler interiors and damaging the building's structure.
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Does all insulation need a vapor barrier?

Vapor Blockers

Vapor barriers—sheets of plastic or kraft paper—keep water vapor out of the wall cavity, so the insulation stays dry. Not every type of insulation needs a vapor barrier. But if it does, the barrier should face inside in northern, heating climates, and outside in humid southern climates.
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Should you put plastic over insulation in crawl space?

A: The plastic cover or vapor barrier is definitely needed, especially in a dirt-floor crawl space. Without a vapor barrier, moisture will migrate to the surface of the soil and eventually cause serious problems in the crawl space, including mold and possibly structural rot. The plastic should cover the entire floor.
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How do you seal insulation?

Seal the gaps with caulk or expanding foam. When complete and dry, push the insulation back into place. Fill wiring and plumbing holes with expanding foam. Caulk around electrical junction boxes, and fill holes in box with caulk.
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Can I leave insulation exposed in garage?

Insulation should not be exposed in the garage if possible. Exposed insulation can cause coughing, itching, general irritation, and can even get in your eyes or lungs. While it's best if all rooms with insulation be covered, the occupied areas are the priority.
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Can you leave foam insulation exposed?

Tests have shown that these laminated boards can withstand UV ray damage for a reasonably long time. That said, it's still advisable to cover any foam board insulation exposed to the Sun within 30-60 days at the most. On most projects, that's more than enough time to finish the exterior walls.
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Can you touch insulation with bare hands?

If you've ever touched fiberglass insulation with your bare hands, you're probably well aware of its effect on the skin. In most situations, touching the material without proper protection will result in a sharp stinging, burning and itching sensation.
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Does fiberglass insulation mold?

Fiberglass, a non-biodegradable substance is resistant to mold. With its sharp, ground glass, mold spores puncture before they can attach to it. Mold can grow on the fiberglass insulation backing, which is made of paper and is a mold food source. Fiberglass insulation without backing may be the best choice.
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Why are vapor barriers bad?

Vapor barriers are supposed to stop vapor diffusion through roofs, walls, and floors. But they can also can trap moisture, causing rot and mold. Where moisture comes from: Water vapor can be forced into wall assemblies from the warm side of the house.
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Where should vapor barrier be placed?

Vapor barriers are usually best installed on the side of the wall that experiences the hotter temperature and moister conditions: the inner surface in colder climates and the outer surface in hot, humid climates. In existing spaces, oil-based paints or vapor-barrier latex paints offer an effective moisture barrier.
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Do I want faced or unfaced insulation?

Unfaced insulation is great for new construction, remodels, walls, floors, ceilings, basements, attics and crawlspaces. It's best used for interior wall applications that do not face the outside and also in rooms that don't need moisture control, like living rooms, dining rooms and studies.
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