Installation Guide

QUESTION: Can Schluter ALL-SET
®
and FAST-SET
®
modified thin-set mortars be used to set tile
over Schluter boards and membranes?
ANSWER: Yes.
All Schluter
®
thin-set mortars, including the ALL-SET
®
and FAST-SET
®
modified varieties can be used to set tile over DITRA,
DITRA-HEAT, KERDI, KERDI-BOARD non absorptive substrates.
QUESTION: How is this possible?
ANSWER: The key is predictability.
Schluter Systems’ modified thin-set mortars have been specifically formulated to set and gain strength in a timeframe that fits typical
installation practice, even when sandwiched between Schluter
®
membranes or boards and porcelain tile. The proportions of cement, water-
retention agents, polymers, and other components in the mixtures were balanced to ensure that extended dry times are not required. This
was validated through both laboratory and practical testing. Now, the installer can select from either unmodified or modified thin-set mortar
to install tiles within our systems according to his or her preference.
QUESTION: Why did Schluter Systems change its position on thin-set mortar?
ANSWER:
We haven’t changed our position on thin-set mortar use within our systems. Developing our own setting materials has given us the ability
to guarantee consistently positive results. And since we control the formulas, we can be sure no changes will be made that have a negative
impact on setting times and strength gain in these environments.
QUESTION: Does this mean I can use other manufacturers’ modified thin-set mortars to install tile
over Schluter boards and membranes?
ANSWER: No.
Our position on thin-set mortar use within our systems in general has not changed. We have no control over the formulation of other
manufacturers’ products and therefore cannot guarantee consistently positive results with their modified thin-set mortars.
QUESTION: Can I still use other manufacturers’ unmodified thin-set mortars to install tile over
Schluter boards and membranes?
ANSWER: Yes.
We still warrant the use of unmodified thin-set mortar meeting ANSI A118.1 to install tile within our systems because we have confidence
in the performance of this product category. This is based on the science of cement hydration and years of positive testing and field
experience.
Please note, if Schluter
®
thin-set mortars are used with Schluter
®
membranes an extended system warranty is available. For full warranty
details, please visit schluter.com/warranty.
ADDITIONAL NOTES
• Remember, all thin-set mortars have an acceptable temperature range that must be observed during application and curing.
• Pre-mixed thin-set mortars and mastics are not suitable for use in conjunction with the Schluter
®
-Shower System.
44 THIN-SET FACTS — Discussion on thin-set mortars and Schluter
®
-KERDI installations