Whether installing flooring systems and coatings in new or existing buildings, substrates generally must first be leveled. The goal is to provide a level and highly resilient surface suitable for a broad variety of flooring systems. In order to achieve excellent bonding to the underlayment, prime the prepared substrate with KOSTER SL Primer. KOSTER SL Primer works as a bonding agent to provide a homogeneous absorbency and bind residual dust to guarantee a consistent and damage free substrate. KOSTER SL Primer cures rapidly and is quickly recoatable. KOSTER SL Premium is then applied in one working step in layer thicknesses between 1/8 and 5/8-in. KOSTER SL Premium is a high quality self-leveling underlayment for the repair of concrete and existing coated floors. The material is characterized by a high compressive strength and cures with almost no shrinkage to prevent cracking. Additionally, KOSTER SL Premium is suitable for non-porous substrates, such as floors that have been coated with KOSTER VAP I® 2000 for moisture control, on existing epoxy coatings, or even tiles. As a bonding agent, use KOSTER VAP I® 06 Primer. KOSTER SL Premium allows for an early use after application: After 3 hours foot traffic is allowed, subsequent flooring systems can be installed after 5 hours, and after 24 hours curing time the material is trafficable.