Repairing Leaks in Concrete/Masonry

Cracks or breaks in concrete or masonry basement walls can turn into active water leaks. Repair leaks and prevent costly damage with the help of QUIKRETE Hydraulic Water-Stop.

Project Instructions:
When working with cement-based products, always wear eye protection and waterproof gloves.

Step 1: Using a masonry chisel, enlarge the crack to a minimum 3/4-inch width and then remove all loose material.

Step 2:
Squarely cut or undercut the edges of the crack. It is important not to create “v” shaped edges as the Hydraulic Water-Stop expands as it hardens.

Step 3:
Mix Hydraulic Water-Stop by adding about 4 to 4 1/2 parts Water-Stop cement to 1 part clean water.

Step 4:
Use a margin trowel to thoroughly mix the material to a heavy putty consistency, making sure that the mix is uniform and lump free. If the mix is too wet, add additional Water-Stop cement and mix thoroughly; if the mix is too dry, add small amounts of water sparingly.

NOTE:Hydraulic Water-Stop sets extremely fast, so do not mix any more material than can be used in 2-3 minutes.

Step 5:
Once a putty consistency is achieved, take a handful of Water-Stop in your gloved hand and begin to work the material into a ball.

Step 6:
Press the Water-Stop cement into the crack using heavy pressure and hold in place for several seconds.

Step 7:
After the material has become “thumbprint” hard, use a margin trowel to trim the patch to match the contour of the surrounding surface.

Step 8:
The Water-Stop repair can be painted after 7 days with a water-based latex paint.

What is needed for the job
  • QUIKRETE Hydraulic Water-Stop
  • Chisel
  • Hammer
  • Wire brush
  • Spray bottle
  • Margin trowel
  • Gloves
  • Safety glasses
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