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Sub Grade
The sub-grade should be well drained and have adequate and uniform load bearing characteristics. It must be moist, completely consolidated, and free of frost at the time of placing concrete. If necessary, it should be dampened with water in advance, but there must be no free-standing water on the sub-grade nor should there be any muddy or soft spots when the concrete is placed. It is recommended that a crusher base or construction sand base be used over the natural soil to facilitate uniform drainage through the underlayment.
Concrete Design Mix
It should contain a minimum of 6 sacks of cement per cubic yard. All fine and coarse aggregates must be totally non-reactive (free of deleterious particles). It is recommended that the coarse aggregate be a minus 3/8", which is satisfactory for most services. Aggregate larger than 3/8" will tend to obstruct the use of the Proline texture mat tools. The water content should not exceed a four inch slump. A retarder-set water reducing admixture should be used, but the concrete must not contain any other admixture, such as calcium chloride or waterproofing additives that contain calcium chloride. All air-entraining admixtures should be used in all concrete that will be subject to freeze-thaw cycles. Since textured concrete has all basic design characteristics of ordinary concrete, reinforcing wire or rebar may be specified. Concrete should be 4" or greater in thickness. For more information regarding mix design of stamped concrete consult your ready mix supplier.
Layout & Design
Textured concrete should be designed in multiples of the size of the Proline texture mat tools. Some allowance should be made, approximately 1/16" for every foot, for possible tool flotation (i.e. an eight foot driveway should be formed to eight feet and ½ inch.) If possible, design the work so as to have the long lines of a given pattern running across the line of sight. This will reduce straight line error, and provide a more pleasant appearance to the work. Establish a reference line. This may be accomplished with the use of a taught line square with a prominent feature or other reference. Texturing is generally run in straight lines, even when walks or drives are curved. An inexperienced individual should not attempt to stamp more than 100 square feet per pour per tool, with a limit of 400 square feet.
Placing Concrete
Prior to placing concrete, surrounding surfaces and walls should be protected to prevent discoloration and to facilitate clean-up. Concrete mix control should be such as to provide good batch-to-batch uniformity. After placing, the concrete should be lightly tamped and wood floated to an even surface which corresponds to the finished grade of plus or minus 1/8" in ten feet in any direction. When concrete is placed and finished in hot or windy weather, precautions must be taken to prevent cracking resulting form excessively rapid drying at the surface.
Coloring
The DUST-ON method of coloring concrete is the most widely used method when texturing concrete, although integral colored concrete is acceptable. When dusting on color, a product such as QC Construction Products color hardener should be used. After the concrete has reached a point when little excess moisture shows at the surface, but while still plastic throughout, the color hardener is applied evenly to the surface by the dry shake method. Water must not be sprinkled or otherwise added to the surface during the application or finishing. The necessary moisture must come from the concrete in order to assure adequate density for the color hardener surface. The first shake should consume two thirds of the material, one third being withheld for the second shake and final touch up. After the first shake, the surface is thoroughly floated. It should not be troweled between the first and second shakes. The second shake is then applied evenly and the surface floated and troweled. A small quantity of color hardener should be withheld from the second shake for touching up non-uniform or weak toned areas if necessary.
Texturing
Using a reference line, begin placing the mats along the reference line moving in any convenient direction. Proper pre-planning and placement of the reference line should enable the work to be completed evenly and expeditiously with a minimum of handwork. At the concrete's optimum degree of set for texturing, great force should not be necessary to press the mat into the wet concrete. Since, time is of utmost importance in texturing, texturing should begin and proceed without delay. Handwork, where necessary, should also commence as soon as possible. Inspect the work for areas which require deepening of the impression or any imperfections that may require correction. This step is performed using Proline texture skins, floppies, chisels or touch-up wheels, which are companion items to the main tool. The hand tools should always be kept for immediate use at the job site. As the concrete approaches its optimum set for starting the texturing process, begin by broadcasting QC powder release agent onto the surface of the concrete using a fan-like motion from left to right just ahead of where you plan to place the first mat. Bubble gum liquid release may be used as a substitute to the powder release. The bubble gum liquid release is a much easier and cleaner method but will leave no secondary color highlights which are achieved with the powder method. Place the first mat in position on the concrete using the pre-established reference line. Using a proline pounder, press the mat straight down into the concrete using no more force than is necessary to press the mat flush into the concrete. Repeat this process by placing a second mat next to the first mat while taking care that the mats are kept tightly together until firmly in place. Repeat this process using as many mats as are on hand. Continue by, picking up and re-placing previously placed mats. Upon completion of the texturing process, recheck your work and do any touch-up work that may be necessary. The textured concrete should then be left to set for at least three days. At the end of this period, the excess powder release (if used) should be washed off the surface of the concrete. Approximately 15-20% of the colored release agent will adhere to the concrete. After the concrete has been allowed to cure for at least two weeks apply a good quality acrylic based sealer such as Calico Stamped Concrete Sealer. This will bring out the richness of the color and prevent the color from fading and staining.
For best results, it is recommended that one texture mat be used per 100 square feet of concrete up to 8 to 10 tools depending on the pattern. For proper alignment, there should be enough tools to span the width of the job plus 2 more tools to begin the second row.
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