Mapei Ultrabond ECO 420 Adhesive

 Mapei Ultrabond ECO 420 Indoor/Outdoor Carpet Adhesive

Ultrabond ECO 420 is a water-based adhesive built for indoor and outdoor broadloom carpet, with high moisture resistance and excellent bond strength for demanding install conditions. Mapei's long-standing recommendation for outdoor carpet over concrete, wood, or fiberglass — pool decks, patios, walkways, and other exposed installs included.

Freeze/thaw stable, so performance holds up through temperature swings. Its unique formulation means it can be installed without moisture testing first — one less step before the job starts. Also suitable for bonding reground rubber underlayments like Mapesonic RM ahead of ceramic tile installs.

Easy to trowel with plenty of open working time, even in warm conditions. Nonflammable, low-odor, and CRI Green Label Plus certified. Includes BioBlock technology, tested to ASTM G21 standards, so it doesn't support mold, mildew, or fungal growth after install (regular cleaning and maintenance still required).

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Do I need to test for moisture before installing? No — the unique formulation lets you skip moisture testing before install.

Can this go on outdoor concrete exposed to weather? Yes — it's freeze/thaw stable and holds up to moisture, making it Mapei's top pick for outdoor carpet over concrete, wood, or fiberglass.

Can I use it for tile underlayment instead of carpet? Yes — it also bonds reground rubber underlayments like Mapesonic RM ahead of ceramic tile installation.

Does it resist mold and mildew? Yes — BioBlock technology is tested to ASTM G21 standards for that.