Stopgap F77 is a solvent-free, two-part epoxy resin waterproof surface membrane designed to control residual construction moisture and rising damp. With a single coat, it impedes moisture up to 98% RH, ensuring reliable installation of floorcoverings even on fast-track projects.

Application: One-coat with 1.5 × 5 mm notched trowel + roller

Working Time:~30 minutes @ 20°C

Cure Time:~3 hours @ 20°C

Moisture Resistance:

• Up to 98% RH (standard)
• Up to 90% RH with underfloor heating
• Up to 85% RH with A2 trowel, 2.5 m²/kg

Installation Method: Applied directly to prepared subfloor; must be fully cured before primers/levelling compounds

Who it’s for:
Flooring contractors, gym fit-out specialists, and installers needing a high-performance moisture barrier for subfloors prior to laying rubber, PVC, vinyl, or carpet gym flooring.

✅ Moisture Control
Blocks residual moisture up to 98% RH in one coat, preventing floor failure.

⚡ Rapid Curing
Cures in approximately 3 hours at 20°C, allowing fast project turnaround.

🔥 Durable Epoxy Protection
Forms a continuous, pinhole-free waterproof membrane for long-lasting performance.

🛠 Easy Application
Pigmented black for visual coverage control. Apply with included 1.5 × 5 mm trowel and roller.

Why it’s superior:

• One-coat system – saves time and labour compared with two-coat membranes.
• High tolerance – suitable for substrates with up to 98% RH moisture levels.
• Compatible with underfloor heating (up to 90% RH).
• Solvent-free, low-odour epoxy resin formulation.

What it solves:

• Prevents damp-related floor failures such as bubbling, lifting, and mould.
• Enables early installation of gym flooring on new screeds.
• Provides a reliable moisture barrier in high-traffic commercial environments.

Available Packaging: 3kg, 7kg, and 14kg kits – resin and hardener supplied in correct ratios for mixing.

Technical Data Sheet