Benefits of using Reflective Foil Insulation for Basement Walls:
- Effective in extreme temperatures - both hot and cold
- Strong, clean, lightweight and flexible
- Safe to handle with no special clothing or breathing equipment
- Cuts and installs easier than fiberglass
- Reflects 93% of Radiant Heat
- Easily stapled, nailed or glued into place
- Waterproof, Non absorbent surface
Basement Concrete Wall InsulationExterior basement wall insulation is not common due to the high cost and difficulty of protecting the insulation from damage. The most common and most inexpensive method of basement wall insulation is the interior method. Traditionally, this method of insulation for basement walls has been executed through the use of fiberglass batts or spray foam insulation. The walls are constructed and the voids between the studs are filled with fiberglass insulation or spray foam, covered with a basement wall vapor barrier like a plastic sheeting, and finally finished with drywall. This method of basement insulation has one very serious problem: Moisture. As the concrete basement wall cures it releases a great deal of moisture. The fiberglass insulation soaks up this moisture, which is trapped by the wall insulation vapor barrier, and any moisture entering the foundation from the outside only contributes to the problem. As the fiberglass begins to saturate it quickly looses its effectiveness. Mold will begin to grow in the fiberglass as well as on the surrounding surfaces, causing the studs and even floor joists to rot. A similar problem occurs with insulation blankets for basement walls.
Fiberglass insulation is porous, and thus susceptible to air filtration, so without a separate vapor barrier, the warm moist air in your basement willl migrate to the cold concrete wall surface and moisture will condense. A much better option for insulation of basement walls is to install a layer of extruded polystyrene (XPS) or some other rigid foam directly to the concrete wall. However, even with XPS rigid foam board insulation for basement walls, you may still have a moisture problem because any polystyrene under 1-1/2" thickness is not considered impermeable enough to be a vapor barrier. The exact perm ratings for any insulation product will vary so you should consult with the insulation manufacturer before purchasing a basement walls vapor barrier.
A "perm", also referred to as a permeability rating is the unit of measurement used to characterize the water vapor permeance of any building material, like insulation. There are several classes of vapor retarders, but according to ASTM E-96, a Class 1 Vapor Retarder has a perm rating of 0.1 or less. All EcoFoil reflective bubble insulation products have a permeability rating of 0.02 - thus making them superior Class 1 Vapor Retarders and an approved basement wall vapor barrier. Check your local building codes for basement walls vapor barrier recommended perm ratings in your area.
A major drawback to several common types of basement walls insulation and basement crawl space insulation, particularly in areas with excessive humidity, is the intolerance to moisture of fiberglass and some foam insulation for basement walls. If the humidity is not controlled, mold, fungi, and odors may develop. A solution would be to use Ecofoil’s bubble insulation in addition to your foam insulation for basement walls. In addition to being resistant to the effects of moisture, EcoFoil’s double bubble radiant foil insulation and single bubble reflective insulation is safe and easy to install. The gap created between the XPS and the drywall creates the air space that you need for the reflection of up to 97% of radiant heat. If you live in a warmer climate zone, XPS foam board is not even necessary. EcoFoil’s Double Bubble Foil has an R value of 8.5, which is a sufficient R-value by itself in warmer climate zones. In conclusion, the best insulation for basement walls and the most effective basement wall vapor barrier is EcoFoil reflective bubble insulation. Along with serving as an approved Class 1 vapor barrier for insulation in basement walls, EcoFoil reflective insulation can have an insulating R-value of up to 8.5 (8.5 is the R-value for our double bubble insulation when installed with a 3.5" air cavity. Double bubble insulation installed with the minimum required air cavity of 3/4" is 6.8. EcoFoil single bubble also has an R-value of 8.5 when installed with a 3.5" air space, and an R-5.8 with a 3/4" air space.) Most valuable of all, EcoFoil or rFoil reflective bubble insulation blocks 97% of radiant heat when used in insulating concrete basement walls or any other space. This means that 97% of the radiant heat from the sun won't get into your home in the summer, allowing you to run your air conditioner less often. And in the winter, the heat you are paying for inside of your home will not be allowed to seep out through poorly insulated basement walls. EcoFoil basement wall insulation and basement walls vapor barrier saves you money and is a long term investment into the future of your home and family.
Download this PDF for basement walls insulation instructions: Basement Wall Insulation Detail - Application Instructions. Or, view the images below.
Basement Walls Insulation - Recessed/Between Studs:
For this application, use Between Joist Bubble Insulation with Staple Tabs. Unroll EcoFoil bubble insulation within the cavity, between the studs. Recess the bubble into the cavity and affix to the studs with a staple gun. The recessed areas on both sides of the bubble insulation provide the necessary air space required to block radiant heat. Install drywall per usual.
Bubble Insulation Installed Over Furring Strips:
Fasten furring strips to wall with shot fasteners or bolts. These furring strips will create your air cavity on both sides of the bubble. Unroll the EcoFoil bubble insulation (any size roll will work) horizontally and staple to the furring strips. Seal the seams with EcoFoil insulation tape. Fasten an additional set of furring strips on top of the bubble insulation to create an air space on both sides, allowing for the reflective properties to work. Attach drywall as usual.
Calculating Square Footage for Interior Basement WallsUse the following calculation to determine your interior wall square footage.
(Height x Width) x 2= X
(Height x Length) x 2= Y
X + Y = Total Square Footage Needed