Should attic insulation face up or down?

Author: Mireya Aufderhar  |  Last update: Thursday, February 20, 2025

Please note that the proper way to install it is to have it installed facing outward or towards the person installing it. Attic specialists look to install it facing downward on your ceiling. Meanwhile, when you're installing it in your crawl spaces, install the insulation facing upward.

Which way should insulation face in an attic?

When installing faced insulation, the facing should always point toward the interior, heated, or air-conditioned space. For example: On exterior walls, the facing should touch the drywall. In attics, the facing should point down toward the ceiling below.

Does attic insulation need to be faced?

You can use faced or unfaced batting when installing between the roof rafters of finished attic spaces. When using paper or plastic batting insulation, that moisture barrier should face outward toward the attic space. Even if the attic space is unheated, it's typically warmer than the outside air in winter.

Does it matter if insulation is faced or unfaced?

For example, if you need extra soundproofing or don't want to spend time installing a separate vapor barrier, then face may be the best option for you. However, if cost savings are more important than convenience, then unfaced may be the better choice in this case.

What is the proper way to install attic insulation?

Step-by-Step Instructions
  1. Choose the right insulation.
  2. Lay fiberglass rolls. Layer rolls of fiberglass insulation perpendicular to the joists.
  3. Create barriers. Use sheet metal or wire mesh to help create a barrier around fixtures or vents. Insulation contacting recessed can lights can cause fire hazards.

Attic Insulation: 3 Common Mistakes to Avoid

Does it matter which way insulation board faces?

Therefore, when installing foil faced insulation always fit the foil side where the temperature difference is greatest. So, any time you use a single side foil insulation, the foil needs to be facing toward the living space.

What is the proper placement of insulation?

In finished attic rooms with or without dormers, insulate (2A) between the studs of "knee" walls, (2B) between the studs and rafters of the exterior walls and the roof, (2C) and ceilings with unconditioned spaces above. (2D) Extend insulation into joist space to reduce air flows.

Can you lay unfaced insulation over faced in attic?

Any new batt or roll insulation added on top of existing insulation in the attic needs to be without a vapor retarder (face). Most vapor retarders on fiberglass are made of kraft paper. The presence of this paper vapor retarder on top of between layers of insulation can trap moisture leading to mold or even rotting.

What is the R-value for an attic?

The recommended R-value for attic insulation can vary depending on the climate zone in which you live. The U.S. Department of Energy recommends attic insulation levels of R-49 to R-60 for most homes in colder climates, and R-30 to R-49 for homes in warmer climates.

What does facing on insulation do?

Faced insulation refers to batt material that has a thin outer layer of paper or plastic, known as a "face". This is used to protect the material, typically fiberglass or mineral wool batts, from humidity, bacteria, and other moisture damages.

Do I need a vapor barrier for attic insulation?

In Most Cases, Attic Insulation Does Not Need To Provide A Vapor Barrier. The good news is that blown-in insulation should not need a vapor barrier. Blown-in is primarily used on the attic floor, and vapor barriers are not a concern for attics in our climate zone.

Is it OK to walk on attic insulation?

The Golden Rule of Attic Safety

These are the bones of your attic, offering the firm support needed to bear your weight. Ignoring this rule and stepping on the drywall or insulation is a fast track to an unplanned ceiling inspection from below, thanks to our unforgiving friend, gravity.

How do you tell if your attic is properly insulated?

Looking across your attic, if the insulation is level with or below the attic floor joists, you probably need to add more insulation. If you cannot see any of the floor joists because the insulation is well above them, you probably have enough, and adding more insulation may not be cost-effective.

Can you over insulate an attic?

While loft insulation is an effective way to improve energy efficiency and reduce heating costs, over-insulating can lead to several potential issues. Firstly, over-insulation can lead to poor ventilation in the attic, which can cause moisture buildup and increase the risk of mould growth.

Where should you not put insulation in the attic?

While it may seem like the more insulation you have, the more energy-efficient your home will be, you do not want to insulate both the attic floor and ceiling. Insulating the floor and the ceiling would create a separate and conditioned environment, especially if you air-sealed your attic.

Is it OK to use R19 insulation in attics?

You will want to bring up your attic up to R-38:

If your attic has 5-6″ of existing insulation, you'll want to install an R-19 to achieve a total of R-38.

Should attic insulation be faced or unfaced?

Faced insulation is ideal for spaces that have no existing insulation, such as exterior walls, attic ceilings, crawl spaces, and exterior basement walls. Please note that the proper way to install it is to have it installed facing outward or towards the person installing it.

How many inches of insulation should be in my attic?

The higher the R-Value, the better the thermal performance of the insulation. The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.

Which way should insulation face in attic?

When installing fiberglass insulation in your home, be sure to put the paper or foil vapor barrier facing toward the heated and cooled living area of the home (down in attics, up under floors, in on walls) to prevent condensation from occurring.

Should you remove old attic insulation before adding new?

Removing old insulation is generally recommended if it's damaged, contaminated with mold, or infested with pests. However, if the insulation is in decent shape and just needs a boost, adding a new layer on top can be a cost-effective option.

Is R30 insulation good for an attic?

Attics are one of the most common areas for R30 insulation. Since heat rises, an uninsulated attic can become a major source of heat loss in winter and heat gain in summer. Installing R30 insulation helps create an effective thermal barrier, maintaining a stable indoor temperature.

Does order of insulation matter?

One of the most important rules of insulation installation order is to install the thickest layer of insulation first, and then add thinner layers on top of it. This is because the thicker the insulation, the higher the R-value, and the more effective it is at preventing heat transfer.

What is the best type of insulation for an attic?

Fiberglass batt is considered to be the best insulation for attics. Compared to other insulation materials, it is the cheapest and easiest to install.

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