synthetic / Foam / Gasket & Filler

Polyethylene foam, closed-cell, various thicknesses (5mm, 10mm, 15mm, 20mm, 25mm, 30mm)

Closed-cell polyethylene foam with excellent water resistance (0.2-0.3% absorption), thermal insulation (0.042 W/m·K), and compression resistance. Available in various densities (32-144 kg/m³) for gasket, insulation, and joint filling applications.

Atlas code
SYN-FOM-GKT-001
syntheticfoaminsulationgasketclosed-cellpolyethylenethermal-barrier
Polyethylene foam, closed-cell, various thicknesses (5mm, 10mm, 15mm, 20mm, 25mm, 30mm)
At-a-glance signals

Closed-cell polyethylene foam with excellent water resistance (0.2-0.3% absorption), thermal insulation (0.042 W/m·K), and compression resistance. Available in various densities (32-144 kg/m³) for gasket, insulation, and joint filling applications.

Overview
Executive summary

Closed-cell polyethylene (PE) foam is a versatile synthetic material characterized by its fine cellular structure with >90% closed cells. This lightweight, resilient foam offers excellent resistance to water, chemicals, and weather conditions. Available in multiple densities and thicknesses, it provides effective thermal insulation, vibration damping, and serves as an ideal material for expansion joints, gaskets, and sill plates in construction applications.

Best when…
  • Excellent water resistance with minimal absorption
  • Wide service temperature range
  • Good thermal insulation properties
  • Lightweight and easy to handle
  • Chemical and weather resistant
  • Non-toxic and safe to handle
  • Available in various densities and thicknesses
  • Can be adhesive-backed for easy installation
Top advantages
  1. 01 Excellent water resistance with minimal absorption
  2. 02 Wide service temperature range
  3. 03 Good thermal insulation properties
  4. 04 Lightweight and easy to handle
  5. 05 Chemical and weather resistant
Top limitations
  1. 01 Not fire retardant in standard form
  2. 02 Requires thermal barrier for interior applications
  3. 03 Limited UV resistance without treatment
  4. 04 Can compress permanently under sustained loads
  5. 05 Environmental data not widely available
Technical
Physical ·3
Density
32-144 kg/m³ Common densities: 48, 64, 96, 144 kg/m³. Source: Manufacturer technical data sheets
Porosity
>90 % closed cells Closed-cell structure
Water absorption
0.2-0.3 % By volume. Source: ASTM test data
Mechanical ·3
Tensile strength
483 kPa For 64 kg/m³ density. Source: ASTM D3575
Compressive strength
90 kPa At 25% deflection for 64 kg/m³ density. Source: ASTM D3575
Flexural strength
Not a primary design criterion; flexural modulus 2000-4000 kPa at 64 kg/m³ kPa Closed-cell PE foam has low flexural stiffness by design; bending resistance is characterised by flexural modulus rather than ultimate flexural strength. For 64 kg/m³ density, flexural modulus approximately 2000-4000 kPa and the material fails gradually in bending without a distinct fracture point. Not typically a design parameter for gasket/joint applications. Source: ASTM D3575 Method W; Sekisui Alveo Stratocell technical data; Sealed Air Ethafoam product bulletin.
Sustainability & Health
Embodied carbon & energy ·2
Embodied carbon
Not available kgCO2e/kg Verified data not found. EPD required for accurate values
Embodied energy
Not available MJ/kg Verified data not found
Compliance & Fire
Fire performance ·3
Combustibility class
Combustible Standard PE foam is not fire retardant. Requires thermal barrier for interior use
Fire resistance level
Not rated hours Must meet flame spread <75 and smoke developed <450 per IBC 2603.3
Flame spread index
<75 Required for commercial use per building codes
Cost & Lifecycle
No cost or lifecycle data recorded for this material.
Layer D

Where it's used

Thermal insulation for walls, ceilings, roofs, and pipes
Expansion joint filler (backer rod) in concrete and masonry
Sill plate gaskets between foundation and framing
Vibration damping and sound insulation
Packaging and cushioning material
Weatherstripping and draft exclusion
Pipe insulation and lagging
SYN-FOM-GKT-001 · Materials Atlas · CLAD Atlas data is reference-only. Verify against manufacturer specifications and current standards before specifying.