1620 Ultra CBF Insulation
Extra tough for over slabs and under flooring. Provides exceptional thermal value and a strong, permanent vapor and radon barrier. The industry’s best choice for concrete applications at 140 PSI compression strength.
140 PSI
Compression Strength
14.2 mil
Bubble Core Thickness
6x Stronger
than Rigid Foam
Methane, Radon & Vapor Barrier





Product Overview
rFOIL 1620 Ultra CBF is a patented under-slab insulation that delivers an exceptional thermal break and a permanent vapor, radon, and methane barrier. Offering nearly six times the compression strength of rigid PE board, it withstands heavy jobsite traffic without crushing or cracking. Ultra CBF typically costs less than two-inch rigid foam, providing builders with a budget-friendly alternative that effortlessly conforms to uneven grades and plumbing obstructions.
Materials
A highly reflective metalized foil sheet sandwiched between two layers of industrial-strength polyethylene bubbles.
Available Sizes
- 48″ × 125′ (Available in square edge)
- 16″ × 125′ (Available in square edge)
- Custom sizes available
Insights
- Choose rFOIL 1620 over 4320 (70 psi) or 4620 (90 psi) when you need maximum compression strength and durability.
- Sealing seams with rFOIL® White Poly Tape ensures a uniform, high-performance insulator and vapor barrier.
- The 1620’s protective laminate covers the reflective layer to prevent degradation from lime and corrosive soil alkalinity.
Warranty
10-year limited warranty. See Warranty sheet below for details.
Certifications & Patents
- RIMA-I Verified
- US Patent No.: 6,562,439, B2
- US Patent No.: 6,514,596, B1
A highly reflective metalized foil sheet sandwiched between two layers of industrial-strength polyethylene bubbles.
- 48″ × 125′ (Available in square edge)
- 16″ × 125′ (Available in square edge)
- Custom sizes available
- Choose rFOIL 1620 over 4320 (70 psi) or 4620 (90 psi) when you need maximum compression strength and durability.
- Sealing seams with rFOIL® White Poly Tape ensures a uniform, high-performance insulator and vapor barrier.
- The 1620’s protective laminate covers the reflective layer to prevent degradation from lime and corrosive soil alkalinity.
10-year limited warranty. See Warranty sheet below for details.
- RIMA-I Verified
- US Patent No.: 6,562,439, B2
- US Patent No.: 6,514,596, B1
Product Benefits
Superior 140 PSI compression strength prevents crushing
Permanent methane, radon, and vapor barrier
Puncture resistant up to 85 psi
Warmer floors and faster slab response times
Withstands heavy, continuous jobsite construction traffic
Cost-effective alternative to rigid foam boards
Protects metalized barrier from corrosive concrete chemicals
Easily conforms to uneven grade and obstructions
Flexible design ideal for edge-slab insulation
Applications
- Under Concrete Slab: Install beneath concrete for maximum thermal efficiency.
- Radiant Heating in Concrete Floor: Optimize thermal response and heat redirecting.
- Radiant Heating in Snow Melt: Maximize performance of outdoor pavement snow-melt systems.
- Radiant Heating over Wood Floor: Energy-efficient barrier beneath wood floor radiant systems.
- Beneath Concrete Over-Pours: Critical thermal block for multi-story over-pours.
- Under Carpet and Wood Sub-Flooring: Insulate beneath finish flooring and sub-floors.
- Edge-Slabs and Expansion Joints: Easily folds upward at perimeter footing to prevent thermal bridging.
Specifications & Literature
Installation Sheets & CAD Details (14)
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Installation sheet: Beneath a concrete slab
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Installation sheet: Radiant heating in a concrete floor
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Installation sheet: Radiant heating in snow melt
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Installation sheet: Radiant heating over wood floor
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Installation sheet: Under carpet
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Installation sheet: Under a wood sub-floor
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Installation sheet: Duct wrap under concrete
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Installation sheet: Beneath a concrete slab
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Installation sheet: Radiant heating in a concrete floor
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Installation sheet: Radiant heating in snow melt
-
Installation sheet: Radiant heating over wood floor
-
Installation sheet: Under carpet
-
Installation sheet: Under a wood sub-floor
-
Installation sheet: Duct wrap under concrete
Brochures (1)
Data Sheets (1)
R-Value Guide (1)
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Installation sheet: Beneath a concrete slab
-
Installation sheet: Radiant heating in a concrete floor
-
Installation sheet: Radiant heating in snow melt
-
Installation sheet: Radiant heating over wood floor
-
Installation sheet: Under carpet
-
Installation sheet: Under a wood sub-floor
-
Installation sheet: Duct wrap under concrete
-
Installation sheet: Beneath a concrete slab
-
Installation sheet: Radiant heating in a concrete floor
-
Installation sheet: Radiant heating in snow melt
-
Installation sheet: Radiant heating over wood floor
-
Installation sheet: Under carpet
-
Installation sheet: Under a wood sub-floor
-
Installation sheet: Duct wrap under concrete