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The preferred method is to scrub the floor with a mixture of Nox-Crete’s Bio-Clean Concentrate CPC diluted 1:2 or 1:3 with water followed by a fresh water rinse. On large floors, the use of an automatic ride-on type floor machine is recommended.

Although a liquid floor hardener can be applied prior to tilt-up panel placement, it is generally recommended that the tilt-up operation be performed first. Duro-Nox can then be applied to the floor after the panels have been raised and the floors have been cleaned. The application of any liquid floor hardener prior to the application of a Silcoseal bondbreaker reduces the bondbreaker’s surface reactivity, which can reduce rain and scour resistance and result in wall panel surface dusting - or in severe cases, stuck panels.

If the hardener must be applied first, ensure the product is compatible with the tilt-up bondbreaker and special precautions are followed during the tilt-up process. Contact us for more details or a specific recommendation.

We don't recommended using another manufacturer's cure and seal with Silcoseal bondbreakers. Both solvent-based and water-based reactive bondbreakers may break down or dissolve components in a large majority of these products, which can result in compatibility issues. If a curing compound or cure and seal is used, it must be removed prior to the application of a Silcoseal bondbreaker. Contact us for specific product recommendations.

An ASTM C309 compliant cure and bondbreaker (when modified for use on a steel troweled surface), such as Silcoseal Select or Silcoseal 2000F can be used to cure the casting surface and for all subsequent bondbreaker coats.

Knowing when a sufficient amount of bondbreaker has been applied between panels to ensure clean separation can be challenging. Unlike traditional tilt-up construction, where it might be a week or longer between placing and finishing a floor/casting slab and the placement of wall panel concrete, in a stack cast tilt-up application, 2-3 wall panels are placed on top of each other within 2-3 days. Due to the lack of time for cement hydration before the placement of additional wall panel concrete, the wall panel concrete is still very porous. This makes it difficult to achieve sufficient bondbreaker holdout on the stacked panel/casting surface(s).

This results in an increased potential for stuck panels. To ensure that an adequate amount of Silcoseal Select is applied between panels, saturate the top side of the panel to receive bondbreaker with water prior to application of the bondbreaker. The water will control the absorption of Silcoseal Select into panel surfaces, providing uniform film holdout.

Because every floor/casting slab is different, it is impossible to state specifically how many coats of Silcoseal Select are required to ensure clean panel separation. Several factors that affect the number of bondbreaker coats required include concrete mix design, finish, weather conditions, size of spray nozzle used, product application rate, and more.

Accordingly, Nox-Crete does not recommend a specific number of coats. Instead, we recommend a visual test to verify adequate coverage of Silcoseal Select. Successive coats of the product should be applied until all treated areas of the casting/floor slab remain uniformly dark in appearance for a minimum of four hours following the previous coat. The development of lighter colored areas on the floor/casting slab within the four hour time window indicates a porous condition requiring an additional coat(s) of bondbreaker. When sufficient bondbreaker has been applied, the floor/casting slab will be uniformly dark in appearance with a slightly sticky, wax-like feel (although Silcoseal Select does not contain any wax) to the touch.