AEROFLEX® Adhesives

Mechanical insulation accessories play a crucial role in the long-term thermal performance of HVAC, refrigeration and plumbing piping, duct and equipment. These specially-designed and engineered components are typically installed at points where the insulation system is most vulnerable – insulation seams, butt joints, termination points and pipe support locations. When the insulation manufacturer’s recommended system accessories are not installed properly (or at all), undesirable outcomes can occur. Examples include excessive condensation build-up, moisture intrusion under insulation, pipe corrosion, saturated insulation, decreased thermal efficiency, mold growth and costly system shutdown and/or failure. For example, closed cell elastomeric foam insulation manufacturers offer a variety of single-source system solutions to ensure long-term thermal performance.

Special-purpose contact adhesives are available in standard solvent-based and low-VOC formulas. Insulation adhesives serve two functions – to bond insulation seams, butt joints and termination points and to provide a vapor seal preventing moisture intrusion beneath the insulation surface. Moisture between the insulation and pipe surface can lead to corrosion under insulation (CUI).

Insulation tapes provide secondary bond & vapor seal protection over glued seams, butt joints, pipe supports and termination points. Elastomeric tapes are commercially available in foam and rubber formulations with a peel-and-stick back. It’s important to be aware that tapes should never be applied over unglued seams. Additionally, tapes should not compress the insulation since compression will cause a loss in R-value while reducing condensation control. For the same reasons, zip ties should never be installed over pipe insulation either.

Pipe hanger locations are a common source of insulation failure for a number of reasons. Due to the installation of inferior (less expensive) materials such as wood blocks, a phenomenon known as “thermal bridging” can occur which causes energy loss and out-of-control condensation. Another cause of failure includes improper vapor sealing at pipe hanger and strut clamp locations. Pipe insulation must be glued to insulated pipe supports with a vapor stop. Although more expensive, insulated pipe supports can be less expensive in the long-run by reducing labor costs and preventing costly system failures.

Fabricating closed cell elastomeric foam insulation to cover equipment such as pipe bends, couplings, flanges, pumps, valves can be time-consuming and costly. Some manufacturers offer factory-fabricated pipe fitting covers for common shapes – 45’s, 90’s, T’s, P-traps, and mechanical grooved fittings. They are typically shipped from the factory fully assembled so the insulator can cut and install on the project. Most importantly, these covers will properly insulate challenging pipe locations while improving the overall appearance of the insulated system.

Closed cell elastomeric foam insulation is subject to UV degradation when exposed to ultraviolet light (natural and artificial). While standard nitrile butadiene rubber (NBR/PVC) formulations will degrade more rapidly than ethylene propylene diene monomer (EPDM insulation) versions, the manufacturer’s insulation coating is either required (NBR/PVC) or recommended (EPDM) in order to maximize the insulation’s life cycle cost for the building owner.

It is a best practice to specify and install a single manufacturer’s insulation and accessories to ensure that their warranty is not voided and ultimately for the protection of a building owner’s investment.