Why You Should Use Closed Cell Foam

The sealed structure of Closed Cell Foam makes it resistant to moisture wicking and able to achieve higher thermal resistance than its open-cellular counterparts. Its isotropic properties deliver consistent performance in any direction.

Closed-cell foam is a resilient, lightweight insulation with a completely sealed molecular structure. Each individual cell is isolated from its neighbors, giving the material unique attributes.

Within closed-cell foam's microscopic structure, tiny pockets of inert gases like air, nitrogen, or carbon dioxide are encapsulated. This closes the cell walls and prevents liquid water or vapor from passing through the material. By contrast, open-cell foams contain interconnecting windows between bubbles that are permeable to moisture migration.

Benefits of Closed-Cell Foam:

Closed-cell foam has several advantages that make it useful for applications requiring effective insulation, moisture barriers, or impact absorption:

Thermal Insulation - The closed cells trap valuable dead air space, achieving an R-value over 5 per inch. This is topped only by rigid insulation boards.

Moisture Resistance - Moisture cannot penetrate the cells, preventing rot, corrosion, or damaging humidity levels behind the foam.

Vapor Barrier - The closed structure works as a vapor barrier, stopping over 95% of inward water vapor diffusion.

Impact Resistance - The flexible, closed cells can absorb shocks to protect surfaces from punctures better than brittle materials.

Temperature Stability - Closed-cell foam maintains its properties across a wide range, from Antarctica to deserts.

Buoyancy - The lightweight, sealed bubbles provide natural flotation qualities useful for marine and safety applications.

Easy Installation - Available with adhesive backing or lightweight for easy cuts/trimming into tight spaces.

The moisture-blocking and insulating power of closed-cell foam's simple yet effective construction makes it a premium building material.

Common Uses for Closed-Cell Foam:

Thermal/Moisture Insulation - Used as underlayment behind siding and around foundations to strengthen the building envelope.

Industrial Piping - Protects and insulates pipes exposed to freezing or high-heat processes like boilers.

Refrigeration - Acts as an efficient insulator for walk-in coolers and freezers, keeping contents fresh.

Flotation Devices - Acoustic Foam Sheet provides buoyancy for watercraft, hot tubs, and swimming pool floats.

Waterproofing - Seals and protects materials like wooden decking that can absorb moisture.

Soundproofing - Absorbs noise and vibration when installed in wall, floor, or ceiling cavities.

Safety Equipment - Components in life jackets, helmets, and padding convert kinetic energy on impact.

Marine Vessels - Insulates hulls and mechanical spaces against harsh ocean conditions.

Versatility has made closed-cell foam indispensable across multiple industries for its moisture-blocking yet breathable nature.

Choosing the Right Closed-Cell Foam:

Density - Light to high-density foams for specific R-values or load-bearing needs. Higher density resists compressing.

Thickness - The project demands certain insulation/flotation thickness. Thinner applications use multi-layering.

Temperature Range - Rated for warmth or cooling; some withstand extreme hot/cold exposures.

Adhesive Backing - Self-adhesive sheets simplify installation vs. adding separate adhesive.

Cutting & Trimming - Ease of shaping into contours or tight spaces with a utility knife or hot wire.

Water Absorption Rate - Completely hydrophobic or minimal absorption for lasting performance.

Toxicity - Virtually all are low-VOC and safe to handle, though some emit formaldehyde.

Pricing - Economical to premium grades available for varied budgets.

Brands like Owens Corning, Tasco, and Smalley provide extensive CCF product lines suited for thermal insulation, vapor barriers, floatation, and more. Choosing the type and supplier ensures a closed-cell foam’s suitability for any job.

Proper Installation of Closed Cell Foam:

Surface Preparation - Clean away dust/debris, fill cracks, and scuff glossy surfaces for adhesion.

Layout - Measure area, and mark/pre-cut foam to fit gaps prior to securing in place.

Adhesive Use - Apply a generous bead onto the back of the foam or substrate per manufacturer instructions.

Installation - Press foam firmly into place, using a plastic smoother or roller to activate the glue and remove air pockets.

Trimming - Use a utility knife to cut excess cleanly at the edges without gapping/tears in the material.

Sealing - Seal seams, edges, and penetration points with compatible caulk to maintain vapor barrier.

Ventilation - When using indoors, allow spaces behind for hot air escape to prevent moisture buildup.

Inspections - Check adhesion periodically, reapplying contact cement as bubbles/gaps emerge over time.

Correct fitting and sealing techniques maximize the performance lifespan of closed-cell foam installations against all weather.