Koster Waterstop - Expanding, Fast Curing Plugging Mortar - W 540 015

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KOSTER Waterstop is a fast curing, expanding plug and repair mortar. Through fast curing and expansion of the curing mortar, a tight bond between the existing substrate and the mortar is achieved. This allows pressurized leaks and leaking cracks to be sealed fast.

Coverage: Approx. 0.4 cubic feet per bag.
Unit Size: 33 lb bucket (W 540 015)

Fields of Application
KOSTER Waterstop can be used to seal water leaks in concrete, masonry, and natural stone structures quickly. It can also be used to install fillets subject to pressurized water, to seal slotted walls, manholes, cable and pipe penetrations, and to seal damaged pipe joints in canal construction, even if exposed to pressurized water.

The substrate must be sound, solid, and free of grease and oil. The area to be waterproofed must not be subject to movement. Remove the area around the leaks at least 3/4-in deep. Dry substrates must be dampened thoroughly before application of KOSTER Waterstop.

Mix KOSTER Waterstop with approx. 3.4 oz/lb of clean, potable water into a stiff, homogeneous mortar. Due to the fast curing time, prepare only small amounts at a time. In the event of water leaks, press the mortar into the cavity firmly for approx. 1-2 minutes (until cured). Substrate temperature and ambient temperature must not be below 40°F. In order to prevent further leaking from the area surrounding the leak, coat the area with KOSTER NB 1 Grey. If the substrate is heavily damaged by salt or moisture, coat the surface with the KOSTER KD System after installation of KOSTER Waterstop.

KOSTER American Corporation is a subsidiary of KOSTER Bauchemie AG of Germany.

Founded in 1982 KÖSTER BAUCHEMIE AG specializes in the development and production of high-quality waterproofing products and systems. Today, KÖSTER forms a group of more than 20 companies with worldwide activities in more than 50 countries. Its headquarters are located in Aurich, Germany.

Our R&D facility, production and technical department are all located on the same campus in Virginia Beach, VA. This allows each department to work closely together to ensure each product conforms to the highest standards of quality. 

KOSTER operates two production facilities in Virginia Beach. The liquid facility produces all of our epoxy coatings while the powder facility produces our self-leveling underlayments as well as other cementitious waterproofing products. 
We place tremendous value on producing our products ourselves in order to ensure the highest level of quality control from development to application. We strongly believe in providing our customers with an excellent and safe experience with our products.