This technical letter provides guidance on setting beds for tile to be placed over surfaces waterproofed with BITUTHENE® or PROCOR®.
There are two basic classes of tile setting beds:
- Portland cement mortar
- Thin set mortar
There are several materials used as thin set mortars such as latex-modified Portland cement and furan. As the name implies, thin set mortars are usually applied less than 1/4 in. (6 mm) in thickness.
There have been instances of poor adhesion of thin sets over some waterproofing systems. We do not recommend using BITUTHENE® or PROCOR® Membranes in conjunction with thin set mortar. BITUTHENE® and PROCOR® Membranes may be used in conjunction with wire mesh reinforced Portland cement mortar setting beds at a minimum thickness of 1 1/4 in. (31.75 mm) as recommended by the Ceramic Tile Institute. A protection layer between the BITUTHENE® or PROCOR® Membrane and mortar is required. Examples include HYDODUCT® 660, 1/8 in. (3 mm) asphaltic hardboard and 1 in. (25 mm) extruded polystyrene.
Please review the standard application procedures found on BITUTHENE® and PROCOR® Membrane Data Sheets.
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Last Updated: 2023-06-28