Waterproofing with Dry-Shake
Krystol Broadcast is a crystalline waterproofing treatment for concrete flatwork. Krystol Broadcast is applied as a dry-shake to the fresh concrete surface and trowelled into the concrete during the final finishing, where it penetrates deeply into the concrete mass. The dry broadcast method produces a smooth finished floor suitable for typical traffic or application of common floor finishes. Krystol Broadcast replaces the need for conventional membrane waterproofing systems, and is best suited for thick concrete slabs that will be power-troweled during finishing.
Not for use on slabs that are subject to flexing or movement. Minimum Portland cement content shall in no case be less than 250 kg/m3 (420 lb./cu. yd.), with w/c ratio no greater than 0.5, and air content no greater than 3%.
Read the Material Safety Data Sheet (MSDS) for this product. For professional use only. Krystol Broadcast becomes caustic when mixed with water or perspiration. Avoid contact with skin or eyes. Avoid breathing dust. Wear long sleeves, safety goggles and impervious gloves
STEP 1: SURFACE PREPARATION
IMPORTANT : Rapid loss of moisture in plastic concrete may impair the abi lity for concrete to receive the dry-shake without subsequent delamination. Use sun/wi nd shades or fogging equipment to protect the concrete surface from drying out before and after appl ying Krystol Broadcast.
- Place concrete as usual following good concreting practices acco rding to ACI guidelines.
- 2. Krystol Broadcast can be applied during finishing — after the concrete has reached its initial set and the bleed water has disappeared.
STEP 2: SPREAD BROADCAST
IMPORTANT : The product must be spread evenly, otherwise may result in uneven color of the finished slab. This can be accomplished by hand spreading with a gloved hand or by using a me chanical drop spreader.
- Spread Krystol Broadcast evenly over the concrete surface at the recommended rate of coverage of 1 kg/m 2 (1.8 lb. /sq. yd.). The fugitive dye will enable the installer to ensure uniform distribution of the product.
TIP : To help attain the proper spread rate, start by laying out the buckets of Krystol Broadcast on the slab in a grid pattern, each 5 paces apart from the next.
- Consult a Kryton representative regarding proper treatment of control and construction joints
STEP 3: FINISHING
IMPORTANT: The high concentration of Krystol will delay the final setting time of the concrete surface. For this reason, the final closing of the surface by hard troweling should be de layed to prevent blistering. Set blades as flat as possible.
- Immediately begin power-floating operations to work the product c ompletely into the surface. At first, the surface may appear dry and appear to be difficult to float. Do not add water. Soon the Krystol chemicals will begin to dissolve and be absorbed by the concrete paste. Eventually the pres ence of Krystol will provide lubrication that will actually make trowelling easier.
IMPORTANT : Do not over trowel – over troweling can lead to blisteri ng and delamination. Blistering may also occur if air content is too high
STEP 4: CURING
- Proper curing is essential to achieve the performance and benefits of Krystol Broadcast. Cure in accordance with ACI 308.1 guidelines.
a. Wet curing the concrete with a fog mist spray, sprinkler or wet burlap for 5 to 7 days is recommended. Protect from rain, excessive wind, and sun.
b. Alternatively, a curing compound conforming to ASTM C309 may be used.
TOOLS & MATERIALS
- Krystol Broadcast
- Power trowel
- Wet curing materials such as fog sprayer
- Optional: Mechanical drop spreader
25 m2 per 25 kg pail (30 sq. yd. per 55 lb. pail)