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Under Concrete Insulation 300 s.f.

Under Concrete Insulation 300 s.f.


1 – 4$129.99
5 – 9$125.00
10 – 19$115.00
20 +$110.00

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Call our product experts at 888-349-3645.

What Is Under Concrete Insulation?

EcoFoil® Under Concrete Insulation is a patented product and a breakthrough in the Concrete Slab Insulation industry. Also called underfloor insulation, radiant floor insulation, under slab insulation, slab on grade insulation, and basement floor insulation, this concrete floor insulation is specifically designed for use as a thermal barrier under concrete. This under concrete insulation works superbly with radiant heated floors, but has many other concrete slab insulation applications. The patented design of this under concrete floor insulation consists of a sheet of metalized polyester with the reflective properties of foil laminated between two layers of strong, compression resistant polyethylene bubbles. Reflective foil insulation as long been used in building applications, but to capitalize on the effects of these reflective properties with an under concrete application requires a unique, patented product for two main reasons. When foil comes into direct contact with soil it can corrode and void the reflective properties of the foil. This is why normal radiant barriers or foil bubble insulation is not appropriate for an underground application. It is also important to maintain an airspace on at least one side of the insulation in order for it to be reflective. By laminating the reflective metalized sheet in between two layers of our sturdy bubble insulation we have ensured the integrity of the foil by protecting it from corrosion and deterioration and we are also maintaining an air space by placing the foil in between the bubble layers. This insulation under concrete product boasts maximum thermal value while also providing excellent reflectivity, keeping your concrete dry and at a uniform temperature. Most importantly, the under concrete barrier insulation reflects 57% of the radiant heat back up towards the surface, whereas without concrete insulation this heat would have absorbed down into and lost in the soil. Ultra Under Concrete Slab Barrier provides a superior radiant and vapor barrier as well as a thermal break. It is also an effective radon barrier if properly sealed with our white poly insulation sealant tape. Insulation under concrete must be sealed with poly tape and not our aluminum foil tape for the reasons mentioned above. This product is also available in a 500 square foot roll of Insulation Under Concrete Slab

Under Concrete Insulation from EcoFoil used as a standalone product will attain an R-value of 3.8 - the highest standalone R rating on the market for an under floor reflective bubble insulation product. Combining this insulation under concrete with a foam board insulation on the bottom can increase the R-value. This is what is done is states requiring an R-value of higher than 3.8 for slab insulation. Remember, however, that foam board insulation alone does not provide a guaranteed termite shield, methane, radon or vapor barrier.

Where Is Ultra Under Concrete Insulation Used?

Under Radiant Heated Floors -EcoFoil Under Concrete Insulation performs superbly when used under concrete slabs with a radiant heating system to help direct heat back into your living space. This under concrete insulation will result in warmer floors and faster slab response times which will reduce the BTU consumption of the radiant heating system, keeping your floors warmer and saving you money on your energy bills. View more information on Radiant Floor Insulation

Under Concrete Slabs without Radiant Heat (Driveways, Snow-melt, Basement Floors, Concrete Basement Walls)- Under Concrete Insulation can also be used under non-heated slabs and will serve as an effective vapor barrier, methane barrier, radon barrier and moisture barrier. In locations where termite infestation might be an issue, the durable metalized sheet within this reflective under concrete insulation will act as a protective barrier to termites and other pests. EcoFoil reflective insulation for under concrete exhibits very low moisture vapor transmission rates, resulting in perm values near zero when tested in accordance with ASTM E 96. When used in concrete floor systems, under concrete insulation performs as a water vapor retarder when the seams are overlapped and sealed with polypropylene tape to form a continuous layer. Under concrete floor insulation will provide a thermal value but each application varies in terms of efficiency.

How is Concrete Insulation Installed?

Find a full list of concrete insulation installation guides Here. Installation of this concrete floor insulation is safe and easy. This under concrete insulator can easily be installed over rough grade, and this insulation under concrete is popular with contractors and builders due to its puncture-resistance bubbles which make it resistant breakage under heavy foot traffic on job sites. This superior under slab insulation is also flexible enough to be easily wrapped and secured around plumbing pipes and wiring. View an info graphic and more information on Concrete Insulation.

An important part of laying concrete is moisture testing. Learn about how to perform a concrete moisture test.

Roll Size: 48"x75' (300 sf). Shipping cost to all zip codes in the contiguous United States is $24.99 per roll of 300 sq.ft. under concrete insulation. Price breaks occur at 5, 10 and 20 rolls. For orders over 5,000 square feet, please call 888-349-3645 for volume discount pricing and a custom shipping quote.

Ultra Under Concrete Insulation Specifications

Download a printable spec sheet for this product: PDF DownloadUnder Concrete Insulation

Nominal Thickness5/16"
Weight1.16 oz/sq. ft.
Temp Range-50F to 180F (ASTM C411)
Emissivity43% (ASTM C1371-04A)
Reflectivity57% (ASTM E903)
Compression Strength140 psi (ASTM D751)
Tensile Strength21.13 lbs/sq. in. (CAN/CGSB - 51.33-M89)
Deflection<10% under 0.5 psi (ASTM 1621)
Puncture Resistance85 lbs/sq. in.
Water Vapor Permeability<0.01 Perms (ASTM E96)
Resistance to FungiDoes Not Promote Growth (ASTM C1338)
Linear ShrinkageNone
FlexibilityNo Cracking (CAN/CGSB - 51.33-M89)
Thermal ResistanceR-3.8 (ASTM C236*)
*ASTM C236 was replaced in 2001 by ASTM C1363. C236 - Standard Test Method for Steady-State Thermal Performance of Building Assemblies by Means of a Guarded Hot Box' and the current standard ASTM C1363-05 - 'Standard Test Method for Thermal Performance of Building Materials and Envelope Assemblies by Means of a Hot Box Apparatus' both test for and demonstrate thermal transmittance in building materials.

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