Water Stop Hydraulic Cement 10 lb.

Quickly and permanently seal active leaks in concrete and masonry with this rapid-setting hydraulic cement. Formulated for both above-grade and below-grade applications, it delivers a dense, nonshrinking waterproof barrier in just 3–5 minutes. Ideal for pools, foundations, cracked walls, pipe collars and other areas where water infiltration is a concern, this cement patch offers long-lasting protection without special tools or additives.

Whether you’re a contractor tackling foundation repairs or a DIY enthusiast patching a basement wall, this blend mixes easily with water to form a sturdy, high-strength filler that resists erosion and washout. Clean the surface, mix to a putty-like consistency, and press into leaks for an instant seal.

Key Features

• Rapid setting: reaches initial set in 3–5 minutes
• Forms a nonshrinking, high-strength plug
• Blocks running water above and below grade
• Ideal for swimming pools, foundations, concrete pipes and masonry cracks
• Simple water-only mixing—no bonding agents required
• Creates a durable, fully waterproof seal

⚠️ WARNING: This product can expose you to Silica, crystalline known to the State of California to cause cancer and Chromium (hexavalent compounds) known to cause birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.