The term "Polished Concrete" is a generic, general term that refers to a process or system of polishing the surface of an existing concrete slab with specially engineered floor grinding machines fitted with diamond tipped blades. The concrete slab is polished, using ever finer grits of diamond blades, until the floor is smooth as a granite counter top. During the polishing process, the concrete is typically impregnated with a sealer that densifies and hardens the concrete surface. The end product is a rock hard, near mirror finish.
There are many methods to polish concrete, many different types of equipment used, and many different types of sealer that can be burnished into the concrete. Due to the various techniques, machines, and sealers that could be used in a typical concrete polishing project, the term "Polished Concrete" can refer to wide variety of quality levels of "polished concrete." When considering installing or pricing polished concrete, it is very important to specify the quality of polish desired.
There are three primary factors that contribute to the quality of the end result of a polished concrete project, namely:
1. The condition of the existing concrete that is to be polished. Large grease or oil stains can be greatly enhanced, but some discoloration will remain. Severely oil stained concrete may be difficult to achieve a very high quality polished floor. Concrete floor flatness and levelness will have an impact on the cost of the project as well as the quality. The density of the concrete will also impact price and quality. Concrete with air entrained will require corrective measures. Holes requiring patching can also impact the quality of shine of polished concrete
2. The type of polishing equipment to be used. There are two types of equipment that contractors are using to polish concrete.
3. Skill and training of the contractor. Polishing concrete is a relatively new science that continues to develop and evolve. To achieve a high quality shine, it is important to select a contractor who has been properly trained in the use of the equipment and chemicals necessary to polish concrete, and to ensure the contractor follows architectural and system specifications.
HTC is an international company headquartered in Sweden and is the industry leader in concrete polishing equipment. HTC has developed a process to achieve the highest quality polished concrete floor possible. HTC has specified the process and procedures for contractors to follow to qualify as HTC-Superfloor installers. The HTC-Superfloor will flatten concrete floors and create a near mirror sheen.
The HTC-Superfloor involves polishing the entire floor a minimum of 9 times, using progressively finer grits of metal and resin bonded diamonds. During the polishing process, a sodium silicate sealer is applied to the concrete and burnished into the concrete.
The result of the HTC-Superfloor process that brings out the natural beauty of concrete and produces a highly reflective surface finish that reduces maintenance and increases durability.
Retroplate is an impregnating sealer manufactured by Advanced Floor Products, based in Salt Lake City, UT. Retroplate is one of many impregnating sealers that can be used during the concrete polishing process. Retroplate has developed a concrete polishing specification, referred to by some architects and designers as Retroplate 99. Advanced Flooring Products certifies contractors on the proper use of the Retroplate chemical and understanding of the Retroplate 99 specification. The Retroplate chemical has gained recognition for advancing concrete polishing chemical technology, and Advanced Flooring Products are continuously updating the concrete polishing body of knowledge. As a result of the contributions to concrete polishing made by the makers of the Retroplate chemical, some architects, designers, specifiers and members of the construction industry use the term "Retroplate" interchangeably with "Concrete Polishing."
Retroplate, like other similar sealers, penetrates the surface of the concrete, reacts with minerals in the concrete to fill naturally occurring air voids in the concrete, thus densifying and hardening the surface of the concrete. Retroplate is the impregnating sealer, only, and does not refer to a process or equipment for polishing concrete. Retroplate can be used in conjunction with the HTC-Superfloor specification. Pacific Decorative Concrete, Inc. are certified installers of the Retroplate product and Retroplate 99 specification.
Any concrete slab can be polished, including interior living spaces and residential garages. However, given the logistics of the equipment required, the need to provide special electrical power requiring a commercial generator, and the hand detail work along interior edges, polishing small spaces can be cost prohibitive when compared to other residential floor finishes, except for the most discerning homeowners desiring a truly unique floor finish. Pricing for concrete polishing depends upon a large number of variables. However, I would expect the price to polish a garage space to be around $10.00 per square foot, with a 600 square foot minimum. For interior residential living spaces, I would expect a price of $16.00 to $18.00 per square foot, which would include decorative staining and decorative boarders and have a 1,000 square foot minimum.
The Benefits of a polished concrete floor versus other typical commercial floorings such as ceramic tile, vinyl tile, carpet, and traditional stained concrete are as follows:
Architectural