Walls using the 20H SYSTEM:
SYSTEM is installed from the positive side of the retaining wall into a
pre-formed joint opening in cured concrete. The joint opening
would be formed with extruded polystyrene that is stripped out from
between the cured joint faces deep enough to receive the 20H foam
(3-inches for 2-inch nominal 20H for example).
The 20H SYSTEM is installed flush to the face of the positive side of
the wall. The below-grade waterproofing membrane and drainage board are
installed over the 20H SYSTEM using the membrane manufacturers standard
inverted, slip-sheet, detail.
While it is not necessary from a waterproofing standpoint to fill the
joint on the interior (negative) side of the wall it is wise to seal
this joint to keep vermin out. The 20H SYSTEM is fine for
this purpose however, if the aesthetic of a black joint filler is a
on the interior.
far as ensuring watertightness is concerned, it is very important to
thoroughly detail and specify the termination of the waterproofing
membrane AND the 20H SYSTEM at the wall footing. It is best to
carry both the membrane and the 20H SYSTEM below the elevation of the
interior floor or slab and into a well-designed drainage perimeter
(gravel, tile, etc.). This will ensure that water running down the
wall in the drainage board and/or on the membrane and 20H SYSTEM is
properly drained away does not back up against the wall.
SYSTEM consists of 20H foam, epoxy adhesive and topcoat.
Permanently elastic, high-density, cellular polyurethane foam,
impregnated with water-based, polymer-modified
asphalt, compressed to approximately 20% of its uncompressed dimension.
Supplied pre-compressed to smaller than mean joint size; installed flush
with, or near to surface into wet epoxy adhesive,
the material expands to seal the joint.
Exposed top surface is treated with Topcoat flexible coating to enhance
sealing and durability.