TOP-CAST® Top Surface Retarder

Expose aggregates the smart way.

Functional and decorative concrete surfaces

With TOP-CAST®, it's possible to achieve an architectural finish with an exposed aggregate look. Our product is more than just a surface retarder — it's a surface retarder that's optimized for robust, consistent performance in all temperature and weather conditions. TOP-CAST® will create perfect, eye-catching flatwork that will satisfy both contractors and customers.


TOP-CAST® Product Documents

Product Name Product Data Sheet SDS/MSDS
TOP-CAST® Top-Surface Retarder
Product Data Sheet
Products & Accessories


  • Product Name
  • Description
  • Key Benefits
  • Applications Type
TOP-CAST® Top-Surface Retarder

Top-Cast® is a water-based, top-surface retarder which does not require covering with plastic for protection. It is available in 11 depths of etch with the color and number coded on the fi nished product for safety and convenience.

Key Benefits
  • Comprehensive range of etch depths
  • Excellent depth of etch control
  • Color coded products
  • Heavily pigmented for ease of application
  • Excellent coverage rates
  • Solvent free, odorless
  • Heat resistance up to 150°F (65°C)
Application Type

Ideal for poured-in-place flatwork and the top surface of precast panels. The wide selection of grades available provides a comprehensive range of eff ects, from a simulated light acid wash or sand blast fi nish up to full exposure of 11/4 in. (32 mm) aggregate.


Sublime ease-of-use for poured-in-place concrete

Surface retarders work by preventing the topmost layer of poured-in-place flatwork from curing. Once the rest of the concrete has cured, contractors can simply wash off the top layer. This achieves a texture that's similar to the effect of sandblasting or acid washing concrete and even deeper exposure, but without any danger to workers or the environment. TOP-CAST® surface retarder has characteristics that make it one of the most effective and easy-to-use surface retarders on the market.

Stands up to the elements

TOP-CAST® surface retarder saves contractors on setup and installation time, and results in a more effective product. In addition, the surface retarder is designed to be extremely stable and robust, with the ability to resist temperatures of up to 150°F. Changes in weather, temperature, and humidity barely affect its efficacy.

Fire-and-forget technology

TOP-CAST® incorporates other innovations that make it extremely easy for contractors to work with. For example, TOP-CAST® is color coded so the appropriate etch depth is easy to identify by contractors. The product will retard to a certain depth, and then deactivate on its own, leaving contractors free to concentrate on other issues.

Nationwide availability

When contractors need TOP-CAST®, it's there for them. At local architectural supply stores, they'll find that TOP-CAST® has twelve different specified depths to produce effects ranging from a barely-there acid-washed sheen to a stony look that's 1 ¼ inch deep. Each variant is color-coded, making it easy to use the right depth and avoid mistakes. For information about TOP-CAST® and how to use it in your products, contact GCP today.

Product Warranty

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