How To Add A Vapor Barrier To Attic

Air sealing an attic.

How to add a vapor barrier to attic.

Most forms of attic insulation benefit from the addition of a vapor barrier to protect them from the harmful effects of moisture which can reduce their effectiveness over time the following are a few simple steps to help you undertake the task properly so your vapor barrier retains heat without damaging the insulation. This means also the access hatch. To assure proper protection of the vapor barrier you will need to cover the entire area of the attic. Avoid adding interior vapor barriers where the outer wall construction already includes a material with vapor barrier properties.

When it comes to the stairway leading into your attic you should heed the advice in this article. You have loose fill insulation in the attic which doesn t have a vapor barrier. A plastic vapor barrier is best installed in a vented attic within climates with over 8 000 heating degree days. And it would not add to much weight to attic size is 550 sq.

You want to add the foil on all surfaces that make up the roof but you also need to keep vents open and clear of the foil. In areas with high humidity such as greenhouses rooms with spas or swimming pools and bathrooms vapor barriers are often recommended. Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers. A vapor barrier in an attic assembly in a severely cold climate with the absence of an air barrier will likely be ineffective.

The goal of adding a radiant barrier in your attic is to cover as much of the underside of the roof as possible. How to install radiant barrier on attic rafters in 5 steps. You will see on which side is the vapor barrier. Over time this trapped moisture can rot the wood framing in your attic or cause mold and mildew to appear.

What you need is an air barrier that is at every step of the way you have to pay attention to airtightness. No you don t need a vapor barrier. On the other hand an air barrier a properly detailed air tight drywall ceiling for example in the absence of a vapor barrier can be effective since it stops the flow of vapor laden air. Most of the blanket insulation types have vapor barriers incorporated and can be very effective if installed properly.

Victorian home much thanks. The theory is that part of the moisture vapor in the house is actually blocked by the drywall and paint on the. Most authorities recommend vapor barriers in certain situations.