Underseal® Underslab Membrane

Underseal® Underslab Membrane is a tough, 85-mil pre-concrete pour waterproofing membrane/vapor barrier designed to virtually eliminate water and vapor transmission through concrete slabs & elevator pitts. In addition to protecting floor finishes and indoor air quality, Underseal® Underslab Membrane also acts as a barrier to methane and radon gas.

Underseal® Underslab Membrane provides a continuous seal underneath the foundation slab. A strong mechanical bond is developed between the membrane and concrete at the time of pouring as the concrete intermingles with the fibers of the nonwoven geotextile. A strong adhesive bond is created when the static load and thermal reactive heat of the concrete slab causes sealant/adhesive compound to have an intimate contact with the concrete surface preventing water migration. Underseal® Underslab Membrane is typically installed horizontally over a prepared subbase such as compacted soil, mud slab or #57 stone. 85 mil Underseal® Underslab can also be used in vertical applications.

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Features & Benefits

Lasting Durability: Tough 3-layer composite membrane - Technology that has stood the test of time.

Outstanding Puncture Resistance: 2 times higher than the new AC 527 building code requirement - Better protection against backfill damage.

Strong Mechanical Bond: Our inner fiberous layer embeds itself into the cured concrete creating a very strong mechanical bond - ensures our waterproofing system will stay in place as the building and outside soil move during the building's lifetime.

Resistant to Water Migration: An adhesive bond is created when heat from the concrete slab while curing , causes our compound to melt onto the concrete's positive side surface creating a continuous sealed floor.

Jobsite Adaptability: Flexible material that adapts to job site irregularities for ease of installation.

Superior Joints: Strong laps seams create a long lasting, water tight system - Outperforms the new AC 527 standard (ASTM 1876) by more than 150%.

Crack Protection: Underslab is thicker than most competitive products giving it stress-absorbing and elongation properties that maintain a watertight seal if cracks develop in the base material or the slab.

Helps Manage Harmful Gases : Acts as a barrier against toxic contaminants methane and radon gas, which may attempt to enter the structure through cracks in the concrete.