Specifications for Patterned Concrete
Part 1 GENERAL
All work in this section shall be PATTERNED CONCRETE® or equal as designated in the plans. The work shall include all labor, materials, equipment and transportation required to install PATTERNED CONCRETE®. The Contractor for this work shall be licensed, tooled and trained by PATTERNED CONCRETE® Industries, Inc.
1.02 Related Work
A. Preparation work, including finish grading (rough grade should be within 1/10 of finish grade), setting forms and screeds, and furnishing and installing of reinforcing steel shall also be done by the Contractor.
B. PATTERNED CONCRETE® Contractor shall also:
1. Provide materials; rebar, concrete, color hardener, sealer.
2. Provide special patented forming tools.
3. Place concrete.
4. Apply color hardener.
5. Apply release agent.
6. Apply patented forming tools.
7. Apply sealer.
8. Perform final cleanup.
1.03 Quality Assurance
A. All PATTERNED CONCRETE® work shall be installed by a PATTERNED CONCRETE® Licensed Contractor who has been tooled and trained by PATTERNED CONCRETE® Industries, Inc.; P.O. Box 691015; Tulsa, Oklahoma 74169-1015; Phone (918)437-6499 or (800)252-4619; Fax (918)437-5150.
B. All PATTERNED CONCRETE® work shall comply with the current specifications and quality standards issued by PATTERNED CONCRETE® Industries, Inc.
C. The PATTERNED CONCRETE® Contractor shall construct a field sample according to specifications to illustrate finished appearance of imprinted concrete. (Optional at additional cost.)
Part 2 PRODUCTS
A. Concrete Mix Design: The concrete shall have a minimum compressive strength of 3000 PSI. Portland cement shall conform to ASTM C150, Type I, II, or V, depending on soil conditions. Aggregates shall comply with ASTM C33. Mixing water shall be fresh, clean and potable. An air-entraining agent complying to ASTM C260 shall be used to achieve an entrained air content for the concrete mix used in accordance with the published recommendations of the Portland Cement Association and the American Concrete Institute (for freeze thaw climates) and/or a normal-set or retard-set water reducing mixture complying with ASTM C494 may be used. Absolutely nothing containing calcium chloride is permitted in the mix.
B. Reinforcing Steel: PATTERNED CONCRETE® recommends a minimum of 3/8 inch diameter reinforcing bars at 24 inches on center each way.
C. Color Hardener: PATTERNED CONCRETE® approved color hardener is used. The particular color shall be selected by the project representative.
D. Release Agent: Dry-Shake powder to facilitate release of imprinted tools. Release agent can match color hardener or be a different color to create a more variegated appearance.
2.02 Concrete Mix
Use 4000 PSI minimum compressive strength in severe freeze thaw areas, 3500 PSI in moderate freeze thaw areas, and 3000 PSI minimum elsewhere. Use higher strength concrete where required by soil conditions or structural design.
2.03 Imprinting Tools
Imprinting tools shall be manufactured by PATTERNED CONCRETE® Industries, Inc.; Tulsa, Oklahoma; Phone (800)-252-4619 or (918)437-6499; fax (918)437-5150. (Substitutions require careful evaluation to assure that imprinting tools provide an acceptable pattern and texture, color will be rich and long-lasting, and installer has adequate training and quality control.)
Part 3 EXECUTION
A. Sub-grade must be prepared according to specifications and is unfrozen and free of frost and standing water.
B. Beginning of installation means acceptance of existing conditions.
A. Layout: Carefully layout form work and joints taking into consideration pattern, intended aesthetics and construction sequence.
A. Forming; Securely install forms and screeds. Assemble to permit easy stripping and dismantling without damaging concrete.
B. Reinforcement: PATTERNED CONCRETE® recommends a minimum of 3/8 inch diameter reinforcing bars at 24 inches on center each way.
C. Concrete mix shall be placed and screeded to the proper grade and wood floated to a uniform surface in the normal manner.
D. Float concrete from two directions with wood floats to create an open and uniform surface. Do not use metal floats.
E. Color Hardener: Apply 40 to 50 lbs. per 100 sq. ft. for light-duty residential work, 60 lbs. per 100 sq. ft. for commercial or institutional applications. Apply evenly in two passes using dry-shake method. Wood float after each shake.
F. Vertical surfaces: Exposed concrete shall be left uncolored except where indicated to be colored on plans (see option below).
a. Option for curbs, risers and planters:
i. Concrete: strip forms as soon as concrete is self supporting. Do not use form coatings that could inhibit adhesion of plaster.
ii. Bonding agents: Apply to concrete.
iii. Plaster: Mix color hardener and water to proper consistency. Trowel apply at a rate of not less than 80 lbs of hardener per 100 sq. ft. and to thickness required by depth of imprinted pattern.
G. Trowel surface with a steel or aluminum trowel; leave no trowel marks.
H. Release agent: Apply even thin coat.
I. Imprint pattern: While concrete is still in plastic stage of set, the patented forming tools shall be applied to make the desired patterned surface. Comply with the manufacturer’s instructions. Layout to proper alignment and imprint to a consistent depth while concrete is plastic. Hand-tool in areas where imprinting tools are not practical.
J. Control joints: Control joints are necessary on most patterns created by PATTERNED CONCRETE®. It is possible that this process may interrupt some patterns. Your PATTERNED CONCRETE® Contractor can consult with you on the best location of these joints in order to produce the most attractive appearance with the most minimal possibilities of cracking. These control joints are to be cut or construction joints. Depth of saw cuts to be ¼ the thickness of the slab. Coordinate joint locations with layout of imprinted pattern.
K. Protect concrete from premature drying, excessive hot or cold temperatures, and damage.
L. Detailing: Chip concrete “squeeze” left from tool placement.
M. Cleanup: Sweep, vacuum or pressure wash surface. For an even, variegated appearance, buff surface. Allow to dry.
N. Sealer: Apply PATTERNED CONCRETE® approved sealer.
Because of the hand-crafted nature of imprinted concrete, minor variations in color, texture and patterns are acceptable.
Note to specifiers:
A specifier is within his rights to issue a proprietary specification which names only one brand. If n the informed and profession judgment of the specifier, his clients’ needs will be best served by naming a particular brand, then he has the responsibility to limit his specifications to one source. This practice is even acceptable on publicly funded projects. This principle to proprietary specifications has found legal support in the case of Whitten Corp. vs. Paddock Poll Builders, Inc.; a Federal District Court case from Massachusetts (37L F. Supp 125). Further support came in 1975 when the U.S. Supreme Court rejected further appeal or review.
Copyright 1997 by PATTERNED CONCRETE® Industries, Inc. A limited
License is extended to qualified design professionals to edit and reproduce this guide
specification to incorporate PATTERNED CONCRETE® into a construction
specification or purchase order.
Issued February, 1997. PATTERNED CONCRETE® Industries, Inc. reserves the right
to revise product specifications and recommendations. Contact manufacturer or local
contractor for current information.
PATTERNED CONCRETE® is a registered trademark of PATTERNED CONCRETE® Industries, Inc.