Tremco PUMA BC LM is a polyurethane-methacrylate (PUMA) base coat. It is a lower modulus version of Tremco PUMA BC, used as the waterproofing membrane for Vulkem EWS and TREMproof PUMA for service temperatures below 32º F (0º C). Tremco PUMA BC LM bonds firmly to Tremco PUMA Primer. It retains its integrity even if substrate movement causes hair-line cracks of up to 1/16" (1.5mm). If cut or damaged, Tremco PUMA BC LM will prevent water migration between itself and the substrate. Tremco PUMA BC LM requires the use of Tremco PUMA Initiator+ for cure.

Low-Modulus Polyurethane-Methacrylate (PUMA) Base Coat used in waterproofing and traffic coating systems, particularly Vulkem EWS and TREMproof PUMA, especially for applications in cold environments (below 32°F / 0°C).

• Base Coat: Tremco PUMA BC LM
• Primer: Tremco PUMA Primer (required for proper adhesion)
• Initiator/Curing Agent: Tremco PUMA Initiator+ (required for curing)
• This base coat is part of the Vulkem EWS and TREMproof PUMA systems, indicating its integration with compatible top coats and detailing materials from these systems.

• Buried waterproofing membrane installations
• Base coat in vehicular or pedestrian traffic coating systems
• Movement joints requiring a low-modulus sealant

• Surface Conditions: Do not apply on damp or contaminated surfaces
• Ventilation: Must be applied with adequate ventilation
• Packaging: 6-gallon pails
• Adhesion: Bonds tenaciously to Tremco PUMA Primer; in adhesion tests, substrate failure occurred with primer, indicating very strong bonding.

• UV Stability: Not explicitly noted; consult system-specific top coat data for UV exposure durability
• Service Temperature: Suitable for cold applications below 32°F (0°C)
• Crack Bridging: Can withstand hairline cracks up to 1/16” (1.5 mm) without loss of integrity
• Waterproofing Behavior: Prevents water migration between coat and substrate if damaged
• Pot Life / Curing Time:
• Dry Time: 1 hour @ 75°F and 50% RH for an 80 mil wet film
• Full cure data not explicitly stated, but system-based guidance likely applies
• VOC Content: 0 g/L (compliant with most stringent VOC requirements)
• Solids Content: 100% solids (no shrinkage on cure)
• Tensile Strength: 991 psi
• Elongation: 420% (ASTM D638), suitable for dynamic movement
• Hardness: Shore A 65, Shore D 18
• Thickness Guidance: Application mentioned at 80 mils wet film in physical properties, which can be taken as a typical or target thickness
• Coverage Rate: Not directly stated in ft²/gal – needs confirmation from system guide or top coat spec
• Temperature Limits: Product is developed for below-freezing application, implying good low-temperature workability

This material is ideal for cold weather or substrate applications where flexibility and waterproofing performance are critical. It is to be used as part of a complete system, particularly Vulkem EWS or TREMproof PUMA, and cannot function as a standalone membrane without proper priming and curing components.

https://jamacsales.com/tremco-puma-bc-lm-22-7l-6g-pail-470371-805-tr400371-00.html