Cover adjacent surfaces to protect from colored concrete splatter. After placing, and initial bull floating or hand floating, no further finishing or application of the color hardener should be performed until the bleed water has dissipated from the surface. Do not use the color hardener product to absorb excess moisture from the concrete surface. SikaColor®-200 Color Hardener is a premium color hardener that typically requires two applications. The first application should be approximately 2/3 of the required amount of color hardener. Once broadcast, allow the color hardener to absorb moisture, slightly darkening, before working the surface with a magnesium or wood float. After bull floating or hand floating, apply the remaining 1/3 balance of the color hardener, concentrating on those areas where the underlying gray concrete color is still visible. Float as before, after it has absorbed moisture. When troweling with power trowels, the use of plastic blades is recommended.
If the slab is too wide to broadcast by hand, bridging the slab or the use of a mechanical spreader may be more efficient. If a mechanical spreader is used, 85% of the color hardener should be broadcast in the first application with 15% being retained for broadcast on any light areas during the finishing operation. Water should never be applied to the color hardener, as it will weaken and discolor the surface. SikaColor®-200 Color Hardener must be correctly applied and finished before the underlying concrete starts to dry and harden. During hot or windy conditions, the use of an evaporation retarder or a finishing aid should be considered.
Texture all surfaces adequately and uniformly for slip resistance. Closing with a steel trowel can diminish the effectiveness of air entrainment at the surface and should be avoided where freeze-thaw is a concern. For exterior installations, apply a broom or swirl finish using a float. When broom finishing concrete, shake off any residual rinse water before brushing the surface. Apply adequate pressure while brooming, but avoid exposing the underlying concrete. Finishing techniques should be consistent and timely to avoid color and texture variations. Interior floors should not be burnished by aggressive hard troweling of the surface. Darkening of the surface may occur. All newly color hardened surfaces should be protected from damage from other trades, liquid spills and foot traffic until the surface is fully cured and sealed. For interior surfaces, consider using Sika® Proguard™ Duracover™ for surface protection.
Stenciling
If SikaStamp® Stencils will be used to pattern the color hardened surface, place the stencils before the initial broadcast of SikaColor®-200 Color Hardener. Stencils should be placed after the bleed water has dissipated and set flat on the concrete surface. Utilize a stencil roller to lay the stencils on the surface of the concrete. Do not push the stencils below the concrete paste. Once the stencils are placed and trimmed, color hardener is applied as previously described. After finishing is complete, the stenciled and color hardened surface can be lightly broomed, floated or textured with SikaStamp® Texture Rollers. Utilize SikaCem®-800 Clear Liquid Release or SikaColor®-300 Antiquing Release when texture rolling the color hardened surface. SikaStamp® Stencils should be removed the same day after installation. Do not leave the stencils on the concrete surface overnight, as this will make their removal time consuming and cause damage to the stencil patterned surface.
Stamping
If the color hardened, surface will be imprinted with SikaStamp® Stamping Tools, SikaCem®-800 Clear Liquid Release or SikaColor®-300 Antiquing Release must be used to act as a bond breaker between the stamp mats and SikaColor®-200 Color Hardener. Imprinting should commence as soon as the surface is firm enough to bear the weight of the installer without excessively deflecting the mat tool, thereby causing depressions in the concrete surface. Stamping must be completed before the surface dries and hardens appreciably, rejecting or minimizing the accurate transfer of the pattern and texture.
Control Joints
Random cracking of a concrete slab is minimized by the timely and correct placement of control joints. Control joints may be introduced during concrete placement with a groover, or after the concrete has reached initial set by power sawing. Each method should be evaluated prior to installation and should be incorporated into the pre-job mock-up. Refer to following American Concrete Institute publications for additional information: Guide to Concrete Floor and Slab Construction (ACI 302.1R-15), Joints in Concrete Construction (ACI 224.3-95).
Vertical Surfaces
On vertical surfaces such as risers or curbs, SikaColor®-200 Color Hardener may be applied onto the freshly placed concrete at the rate of 70-90 lb./100 sq. ft. (31.8-40.8 kg/9.3 m²). Do not exceed a thickness of ¼ in. (6.4 mm). SikaColor®-200 Color Hardener must be mixed with water to a consistency of mortar and applied onto surface prior to the concrete curing completely, typically the same day of the pour and as soon as the verticals surfaces can be stripped of forming without slumping. Once the material is applied, employ the same finishing techniques that were utilized on the adjacent horizontal surfaces.
Patching or Repairing Cured Concrete
SikaColor®-200 Color Hardener may also be used to repair cured concrete surfaces. On cured vertical or horizontal surfaces, it is important to clean and profile the surface to be repaired to a Concrete Surface Profile of CSP 2-3. Be sure all curing and sealing compounds have been removed and the area is thoroughly dry. Apply a bonding agent such as SikaCem®-170 Primer to the area of repair prior to repair application. Follow the bonding agent instructions before mixing the SikaColor®-200 Color Hardener slurry. Mix approximately 2 lb. (0.9 kg) of SikaColor®-200 Color Hardener with 1/2 cup of clean water to a consistency of mortar. Mix water can be adjusted to accommodate the installation. Do not exceed a thickness of ¼ in. (6.4 mm). For areas exceeding ¼ in. (6.4 mm), first utilize a compatible cementitious patching material to repair the areas within ¼ in. (6.4 mm) of the surface. Then proceed to priming and patching. Once the material has been applied, finish and texture to match surrounding area. Surfaces to be repaired should not be below a temperature of 50°F (10°C) and not exceed a temperature of 80°F (26.7°C). Avoid using SikaColor®-200 Color Hardener as a patch in direct sunlight or in strong wind. It may be necessary to cover repair areas with a curing membrane to avoid drying shrinkage cracks under certain conditions.
CURING AND SEALING
Use SikaCem®-100 Clear Guard®, SikaCem®-100 PRO 350®, or SikaCem® water-based sealers for exterior applications. Use SikaCem® water-based sealers for interior applications. Consult the most current SikaCem® sealer local Product Data Sheets for complete Application Instructions.
Do not apply sealers to concrete substrate with moisture levels > 6% mass (pbw – part by weight) as measured with Tramex® CME/CMExpert type concrete moisture meter.