QA

How To Install Exterior Wall Insulation

How do you install insulation on outside walls?

Which way should insulation face on exterior wall?

(The general rule for insulation is that the facing always goes toward the conditioned space.) The second layer of insulation should be unfaced so that moisture doesn’t collect between the layers.

What side of insulation faces out?

Hi Kim, Regardless of whether fiberglass insulation is installed in a wall, attic, or crawlspace; the paper facing should always face toward the inside of the home. That’s because the paper contains a layer of asphalt adhesive which prevents water vapor from passing through it.

What happens if you put insulation in backwards?

So if it is installed upside down, the paper moisture barrier can actually keep moisture in-between the paper and the sub-flooring. This can lead to mold issues, as well as structural deterioration. Also, the paper is flammable so not properly installing it can create a fire hazard.

What is the difference between faced and unfaced insulation?

The Difference Between Faced And Unfaced Insulation Faced just means that kraft paper is attached to the insulation itself. The paper helps improve the sturdiness of the insulation so it doesn’t fall down as much. Unfaced insulation is just as good as faced, but it doesn’t have that paper attached to it.

Can you put faced insulation over faced insulation?

Can you put faced insulation over faced insulation? No, faced insulation should not be added over existing insulation since the vapor retarder on top of or between layers of insulation can trap moisture.

Is it worth insulating exterior walls?

Exterior Wall Insulation This is more expensive and usually requires a contractor, but it may be worth the cost—especially if you live in a very cold climate. These materials literally have insulation built in, and houses built using these products often have superior insulating qualities and minimal thermal bridging.

Why does insulation have paper?

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.

Where should faced insulation be used?

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. It should fit snugly into the space but shouldn’t be compressed.

Can rigid foam board be left exposed?

Q: Can FOAMULAR® be left exposed in interior applications? A: No. To comply with building codes, all foam plastics must be covered with a 15 minute thermal barrier.

Does insulation have a vapor barrier?

Vapor barriers applied over the face of the insulation provide additional benefits in the fight against moisture. Usually composed of a thin film, such as polyethylene, vapor barriers are used to retard or prevent water vapor diffusion into a wall, ceiling or floor during the cold winter.

How do I know what insulation to use?

Measure the area needing insulation. Measure the length and width of the area you need to insulate. Multiply the length times the width to determine the square footage of the space. Decide on the type of insulation to use.

What type of insulation is best for walls?

In most wall applications, you will use R-13 or R-15 kraft-faced fiberglass insulation rolls for these two-by-four stud walls. While rated differently, these two types of insulation are close enough in thickness that they can both fit into modern two-by-four wall systems.

Is R19 insulation better than R13?

There is a direct relationship between the amount of insulation and the amount of heat transfer. The bigger the R value, the better the insulation is at slowing down the heat transfer. So R19 is better insulation than R13, and R30 is better than R19. The larger the R value, the better the insulation value.

Should you remove old insulation before adding new?

Your insulation needs to be removed along with the droppings, as it’ll carry some of its toxicity if left in your attic. Removing old insulation and replacing it with new ones will not only rid your home from any rodent infestation and mold, but also improve its energy efficiency and overall air quality.

Can you put 2 layers of insulation?

Doubling the thickness of insulation will double the insulation’s R-value, cutting heat loss in half. Each time the insulation layer is doubled in thickness, this rule applies. In some cases, like an attic, it’s worth piling on more insulation because there is plenty of room.

Do you only insulate exterior walls?

In addition to the exterior walls, you should also insulate any walls between the living space and unconditioned areas like garages or attic storage spaces. If you’re adding a room or finishing a previously unfinished area, be sure to insulate the exterior walls.

Can you insulate an old house from the outside?

One way to insulate walls of an old house is to focus on the home’s exterior: Apply a house wrap/vapor barrier to exterior walls. Attach 1-inch foam board insulation. Install siding over the insulation.

Can you over insulate a house?

It is possible to over-insulate your house so much that it can’t breathe. The whole point of home insulation is to tightly seal your home’s interior. But if it becomes too tightly sealed with too many layers of insulation, moisture can get trapped inside those layers. That’s when mold starts to grow.

What is a good R value for exterior walls?

Typical recommendations for exterior walls are R-13 to R-23, while R-30, R-38 and R-49 are common for ceilings and attic spaces. See the Department of Energy’s (DOE) ranges for recommended levels of insulation below.

How do you keep insulation from falling down?

Use metal installation hangars or nylon straps to keep your insulation from falling down. You can buy these at your local hardware store, big-box store, or make them with your own wire. Just make sure the wire is galvanized with pointed ends to get them to stay in between the joists.