QA

Quick Answer: How Thick Foam Board For Basement Walls

The thickness of foam insulation in basement walls will range between two to seven inches, depending on where you live and whether you use open or closed-cell spray foam insulation.

What thickness foam insulation do I need?

Now generically speaking, we usually recommend open cell spray foam to be 6- to 10-inches on a roof deck or ceiling and 3-inches in the walls. Closed cell spray foam should be 4- to 5- inches on the ceiling and 2- to 3-inches in the walls.

What kind of insulation is best for basement walls?

Spray foam is probably the best possible insulation material for basements and damp areas. Closed cell spray foam is perfect for locking “out” the water vapor that inherintely wants to migrate from your damp basement walls to your finished basement rooms.

What R value should basement walls be?

The Model Energy Code recommends R-11 insulating values for basement walls in most of the country and R-15 for the northernmost states.

What is the R value of 2 inch foam board?

A wall utilizing STYROFOAM T-MASS Technology with a 2-inch exterior layer and a 4-inch interior layer of concrete along with a 2-inch layer of STYROFOAM extruded polystyrene insulation would result in a material R-value of approximately 11.33.

How thick should spray foam be in basement?

You will have to decide based on your budget but as a rule of thumb we say, living space needs 3” and storage space can get away with 2”. Let’s face it, 2” of spray foam insulation from top to bottom is going to outperform anything else on the market; 3” is just a bit better yet.

What is the R-value of 1 inch foam board?

R-values can range from 3.6 to 4.2 per inch.

What is the R-value of 4 inch foam board?

Foam Board Insulation R-Value per inch Thickness (in Inches) R-value (in I-P/Imperial) RSI (R-value in Metric) 2.5 15.5 2.7 3.0 18.6 3.24 3.5 21.7 3.78 4.0 24.8 4.32.

What is the cheapest way to insulate basement walls?

The smart and inexpensive way to insulate joist bays is to use extruded polystyrene (XPS) foam insulation panels cut to size to fit inside the bay and “glued” in with expanding foam. When the expanding foam hardens, trim away the excess and cover the foam with a piece 1/2″ thick drywall to meet fire code.

Should you insulate your basement walls?

Insulating your basement may seem like a project best suited for another day, but truthfully, insulating your basement walls can help improve comfort and reduce energy and maintenance costs to HVAC systems. It also allows for extra living space within a home, which can be invaluable.

Should you insulate concrete basement walls?

Walls. Basement walls should be insulated with non-water sensitive insulation that prevents interior air from contacting cold basement surfaces—the concrete structural elements and the rim joist framing. The best insulations to use are foam based and should allow the foundation wall assembly to dry inwards.

Should you put a vapor barrier on basement walls?

Basement Remodeling Ideas from TV While a vapor barrier won’t stop moisture from making its way between the foundation walls and the actual barrier, it will help prevent water from coming into the basement. This, of course, helps to dissipate moisture and mold – two things that no one wants to see in a basement.

Do you need to insulate basement walls below grade?

Your best bang for the dollar in this instance is to insulate the coldest part of the wall, again typically to 2-feet below grade. However, there are many instances where insulating the full wall is the best option, such as if your walls are stone, or the floor is earth or crushed stone with no vapor barrier.

How thick is r30 insulation?

8¼ ” thick, R-30C EcoTouch® Thermal Batt insulation prevents moisture damage and helps assure long roof life by providing 1″ of ventilation air space between the insulation and roof deck.

Do you need a vapor barrier with rigid foam insulation?

What I recommend to create a thermal break in basements is rigid foam insulation, with TUCK tape and no vapour barrier. Tuck tape all seams AND, be sure to use a spray foam in all the corners. You don’t need vapour barrier, and you won’t need to insulate between the studs.

Which side of foam board insulation faces out?

If you’re wondering whether to put the foil side of foam insulation board shiny side in or out, consider whether you want to make the space inside warmer or cooler. If you want to make the space warmer, the foil should face inside so it can reflect radiant heat back into the room.

What is the difference between pink and blue foam board?

Main Difference Between Pink And Blue Foam Boards The two products also have the same insulating power. However, blue foam boards are manufactured by Dow Chemical Co. whereas the pink foam boards are manufactured by Owens Corning company. The boards are marketed under different brand names.

Can you put rigid foam insulation between studs?

Rigid foam board insulation can be used throughout the home, but most often it is found in basement walls. The correct method of using rigid foam is to run continuous 4-foot by 8-foot sheets of the foam across the concrete basement wall between studs.

Is R10 enough for basement?

R10 is adequate for a basement, assuming all the walls are below ground. 2 inch thick foam generally gives R10.