Surface Preparation

  1. The concrete surface to be treated must be clean and free of laitance, dirt, film, paint, coatings or other foreign matter. The surface must also have an open capillary system to provide “tooth and suction” for the Xypex treatment.
  2. If surface is too smooth (e.g. where steel forms are used) or if surface is covered with excess form oil or other foreign matter, the concrete should be lightly sand-blasted, water-blasted, or etched with muriatic (HCL) acid.
  3. Horizontal surfaces should have a rough wood float or broom finish. Concrete laitance must be removed from surface by light sand-blasting, water-blasting or etching with muriatic (HCL) acid.
  4. Surfaces to be etched with muriatic acid should be dampened with water before application of the acid. 
  5. After acid etching flush concrete thoroughly with clean water.

Structural Repair

  1. Rout out cracks, faulty construction joints and other structural defects to a depth of 1.5 inches (37 mm) and a width of one inch (25 mm).
  2. Apply a brush coat of Xypex Concentrate (as described below) in cavity and allow to dry for 10 minutes.
  3. Fill cavity by tightly compressing Dry-Pac into the groove with pneumatic packing tool or with hammer and wood block. (See below for Dry-Pac mixing instructions.)
  4. Against a direct flow of water (leakage) or where there is excess moisture due to seepage, use Xypex Patch’n Plug in lieu of Dry-Pac followed by a brush coat of Xypex Concentrate. For expansion joints or chronic moving cracks, flexible materials such as expansion joint sealants should be used.
  5. Refer to Xypex Repair Procedures for more detailed instructions.

Wetting Concrete

Xypex requires a saturated substrate and a damp surface. Concrete surfaces, therefore, must be thoroughly saturated with clean water prior to the application so as to aid the proper curing of the treatment and to ensure the growth of the crystalline formation deep within the pores of the concrete. Remove excess surface water before the application. If concrete surface dries out before application, it must be re-wetted.