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How to Use HD-150

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If concrete walls and floors are moist or wet due to water seepage through the pores of the concrete, then XYPEX HD-150 can simply be applied with a brush to the concrete surfaces. However, if water seepage is occurring through construction joints (where the floor and walls meet), cracks or other defects, then these areas must be repaired prior to applying the Xypex coating.


(1) Chisel or chip out a rectangular "U" shaped groove (not "V" shaped) along crack or construction joint. For best results, groove should be approximately 1" wide by 1" deep.

(2) Remove all loose debris from groove by flushing with water and scrubbing with a stiff bristle brush.


Fill groove with Xypex Patch'n Plug or other fast-setting hydraulic cement compound available at building supply stores (to enhance its waterproofing characteristics blend 3 parts hydraulic cement with 1 part HD-150).

(4) Apply HD-150 coating over the repaired area and to the concrete surface in accordance with directions below.


Once leaky cracks and construction joints have been repaired, the waterproofing of walls and/or floor can be undertaken by applying a slurry coat of HD-150 to the concrete surface. To ensure best possible results, follow the application instructions carefully (detailed application procedures can also be found inside the container). Coverage for one coat is approximately 6 sq. ft. per lb.

(1) Surface Preparation
  A clean, open-pore surface is required. Remove any substance (e.g. dirt, oil, paint etc.) that could prevent the penetration of HD-150's crystalline growth deep within the pores and capillary tracts of the concrete or concrete block. Smooth steel-trowelled concrete (e.g. some floors) must be roughened or etched to provide proper "tooth and suction" for the HD-150 treatment.

(2) Wetting the Concrete
  Moisture is also required for HD-150's chemical ingredients to penetrate and crystallize deep within the pores of the concrete. Therefore, dry concrete must be thoroughly saturated (soaked) with clean water before application of the HD-150 coating. This can be accomplished by spraying with a hose or garden sprayer, or by filling a pail with water and brushing the water onto the concrete surface. Excess surface water should be removed prior to application.

(3) Mixing
  Mix 5 parts HD-150 powder with 2 parts clean water (by volume) until a thick creamy consistency is obtained (a paddle mixer on a slow speed drill may be used for larger batches). Mix only as much as can be applied in 10-15 minutes. If mix starts to set, agitate briefly but do not add more water. Protect hands with rubber gloves.

(4) Application
  Apply slurry mixture with a thick nylon bristle brush (cement brush) or push broom for large horizontal surfaces. The mixture must be uniformly applied and should have a thickness of 1/16" (1.25 mm). When a second coat is required (e.g. concrete block walls), it should be applied after the first coat has set but is still "green" (less than 48 hours). Spraying a light mist between coats may be necessary to prevent premature drying. HD-150 cannot be applied outdoors in rain or freezing weather (see Limitations).

(5) Curing
  The curing process is important for the growth of the crystalline formation and proper hardening of the coating. Curing should begin after the coating reaches an initial set and begins to dry (normally 1-2 hours). Cure by spraying the coating with a fine mist of water or apply water from a pail with an applicator brush. Under most conditions it is sufficient to dampen the HD-150 treatment three to four times a day for 2-3 days.

Care must be taken to prevent puddling of water over the HD-150 application on floor applications. In cool, damp conditions, water curing of the coating may not be necessary. In hot dry conditions the treatment will need to be dampened more frequently to prevent premature drying.


XYPEX CHEMICAL CORPORATION warrants that the products manufactured by it shall be free from material defects and will be consistent with its normal high quality. Should any of the products be proven defective, the liability to XYPEX shall be limited to the replacement of the product ex factory. XYPEX MAKES NO WARRANTY AS TO THE MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE AND THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED. User shall determine the suitability of the products for their intended use and assume all risks and liability in connection therewith.


XYPEX and HD-150 are trademarks of Xypex Chemical Corporation.
© 2002 Xypex Chemical Corporation. All rights reserved.