Sanyi uncoupling membrane is specifically designed to allow the installation of ceramic and stone tile over any even and
load-bearing substrate and an underlayment for ceramic and stone tile. This plastic membrane system geometrically configured to
provide air space between the tile and the substrate to allow independent movement between the two and limit the transfer of the
stresses." SANYI UM503 is a polyethylene membrane with a grid structure of square cavities, each cut back in a dovetail
configuration, and an anchoring fleece laminated to the underside. The anchoring fleece is embedded in thin-set mortar to provide
a mechanical bond to the substrate. Tile is installed over UM503 using the thin-bed method in such a way that the mortar becomes
mechanically anchored in the square, cutback cavities of the matting. Designed specifically for ceramic tile and dimension stone
installations, UM503 serves as an uncoupling layer, waterproofing membrane, and vapor management layer that accommodates moisture
from beneath the tile covering. Further,UM503 performs all these functions while still providing adequate support/load
distribution for the tile covering. The combination of these four essential functions allows for the successful installation of
tile over a wide range of substrates, including plywood/ OSB, concrete, gypsum, heated floors, etc.
The integration of this uncoupling, waterproofing, load-distribution, and vapor management functions makes consistent results
viable. Cardinal Principle:
The concern with concrete is that the concrete slab contains large amounts of residual moisture that still need to be released
from the concrete. This release of moisture can affect the curing of the mortar and the grout, and in the case of many crack
isolation/waterproofing membranes, especially those membranes that are flat, they have limited resistance to pressure from
moisture as there is nowhere for the moisture to be released. This release of moisture in turn creates pressure which can cause
the membrane to bubble or de-bond from the concrete slab. An uncoupling membrane must have free space or empty cavities on the
underside of the membrane which inherently allows for moisture/vapor release and eventually equalization.