TekFoil Buyer's Guide
What types of TekFoil Reflective Insulation do you offer?
Reflective/Bubble Bubble/White Poly
How does TekFoil Reflective Insulation work?
Radiant heat travels from warm surfaces to cool surfaces take the sun heating the earth, for example. TekFoil Reflective Insulation has 0.97 reflectivity. This means it prevents radiant heat transfer by up to 97% and 0.03 emissivity, which means it allows only 3% of heat to get into or out of your building. Compare this to other types of insulation, such as fiberglass and foam, which allow 80-90% of radiant heat to pass through. Preventing radiant heat transfer is necessary for energy-efficient buildings, because this type of heat transfer accounts for up to 90% of heat gain in the summer and up to 75% of heat loss in the winter.
One "Bubble" in the TekFoil description means that it is constructed from one layer of polyester bubbles between two reflective layers or a reflective layer and a white poly layer. "Bubble Bubble" TekFoil is constructed from two layers of polyester bubbles between two reflective layers, or a reflective layer and a white poly layer.
What does "Reflective" and "White Poly" mean?
Reflective/Bubble/Reflective and Reflective/Bubble Bubble/Reflective TekFoil is comprised of either a single layer or double layer of bubbles between two layers of coated metalized polyester. Reflective/Bubble/White Poly and Reflective/Bubble Bubble/White Poly TekFoil are made of either a single or double layer of bubbles between a layer of coated metalized polyester and a layer of white poly.
What's the difference between TekFoil without bubble layers and TekFoil with bubble layers? Where should I use which type?
TekFoil without bubble layers, such as Reflective/Kraft and Reflective/Reflective, is ideal for use on the attic floor and as housewrap. Both types are available perforated, which lets moisture escape, and can be used with an existing vapor barrier. TekFoil with bubble layers, such as Reflective/Bubble/Reflective and Reflective/Bubble/White Poly, can be used in a variety of locations throughout your home or building, including walls, ceilings (under drywall), around heating ducts, crawl spaces and with radiant heating systems. TekFoil with bubble layers makes an ideal vapor barrier. Please note, when using TekFoil under concrete, you must use TekFoil with White Poly side facing the concrete.
Why should I choose "Bubble Bubble" TekFoil?
"Bubble Bubble" TekFoil, such as Reflective/Bubble Bubble/Reflective and Reflective/Bubble Bubble/White Poly, is ideal for use when you're not using TekFoil in conjunction with another type of insulation. Examples of this would be garages, crawl spaces and agricultural buildings. You also may want to choose "Bubble Bubble" TekFoil if you live in a cold climate, such as the Northern United states, or for installation in a wood-frame or steel-frame building.
What type of TekFoil should I use under concrete?
When installed under concrete, you must use either Reflective/Bubble/White Poly or Reflective/Bubble Bubble/White Poly with the White Poly side facing the concrete. The White Poly layer protects the TekFoil from the lime in the concrete, which can degrade the reflective layer.
Should I install TekFoil Reflective Insulation with an air space? How should I do this?
For TekFoil insulation to be most effective, an air space of 3/4" should be left on at least one side of the insulation. This is necessary because TekFoil is designed to inhibit radiant heat transfer. The most effective way to install TekFoil is to leave a 3/4" air space on each side of the insulation. If this is not possible, a 3/4" air space between the insulation and the other building material, such as drywall or roof, is the second most effective approach. In warm climates, the air space should be toward the outside. If you cannot install with an air space between the insulation and the other building material, you can install TekFoil directly against the material with the air space on the other side. An example of this is installing TekFoil directly against roof boards versus installing it underneath rafters. While there is no air space to allow the TekFoil to reflect radiant heat, the emissivity of TekFoil does not change. This means that TekFoil still allows only 3% of radiant heat to pass into or out of your building.
Should I install TekFoil Radiant Barrier on the roof or on the attic floor?
Generally, if you live in a hotter climate, your best bet is to install TekFoil Radiant Barrier on the roof. However, because of the slope of your roof, you need more TekFoil for the roof versus the attic floor and you also need to cover the gable ends. In cooler climates, it is more beneficial to install perforated TekFoil on the attic floor, because it will also decrease heat loss during the winter.
How should I install TekFoil on the roof?
Whether you are installing TekFoil with bubble layers or TekFoil Radiant Barrier, you should aim to install it with at least a 3/4" air space. The best way to get this air space is to run TekFoil across the rafters. This method also saves time cutting and stapling. Another method is to install TekFoil between the rafters, but with an air space between the TekFoil and the roof. Use this method if you are planning to finish your attic. Please note: If you install TekFoil Radiant Barrier on your roof, you must leave a gap of at least 3" to 6" at the peak and at the eaves to allow for ventilation.
When using TekFoil R/B/R or R/BB/R in your walls, you will have to install in conjunction with bulk insulation, such as fiberglass or cellulose. TekFoil should be installed with the air space on the warm side of your house. This means if you live in a warmer climate, the air space should be between the bubble and the bulk insulation. If you live in a cooler climate, the air space should be between the TekFoil and the drywall. Because R/B/R and R/BB/R are vapor barriers, you will want to cut 6" slits in the kraft paper vapor barrier of fiberglass insulation after it is installed. Then you can install TekFoil as described.
What do I do if I can't get an air space in my walls?
There are a couple options, depending on the thickness of your wall studs. If you have 2x8 studs and are using regular 6" bulk insulation, you can push it far enough back and install TekFoil either over or between the studs for an air space. With 2x6 or 2x4 studs, you will not be able to have an air space with 6" bulk insulation. You can use furring strips every 16" perpendicular to the studs (and also at the top and bottom of the wall) to create an air space and then install TekFoil over the strips.
Can drywall be installed right over TekFoil?
Yes, drywall can be installed right over TekFoil. TekFoil will be able to support the drywall without causing waves. Puncturing or compressing the bubbles is not an issue. It will be harder to install the drywall, because you won't be able to find the studs as easily. Once you find them, measure the distance between them and then mark lines on the drywall.
What can I do with the extra TekFoil I have?
Insulating your garage door, water heater or heating and air conditioning ducts are the most obvious answers. Some other applications include cooler liners, seat warmers, insulating sheds and dog houses, putting under sleeping bags and more.