- Polished concrete - The act of changing a concrete floor surface, with or without aggregate exposure, to achieve a specified level of gloss using one of the listed classifications; Bonded Abrasive Polished Concrete, Burnished Polished Concrete, or Hybrid Polished Concrete.
- Bonded abrasive polished concrete - The multi-step operation of mechanically grinding, honing, and polishing a concrete floor surface with bonded abrasives to cut a concrete floor surface and to refine each cut to the maximum potential to achieve a specified level of finished gloss as defined by the CPAA. This yields the most durable finish and requires the least maintenance.
- Burnished polished concrete - The multi-step operation of mechanical friction-rubbing a concrete floor surface with or without waxes or resins to achieve a specified level of finished gloss as defined by the CPAA. This operation yields a less durable finish and requires more maintenance than bonded abrasive polished concrete.
- Hybrid polished concrete - A multi-step operation, using either standard grinding / polishing equipment, lightweight equipment, high speed burnishing equipment, or a combination of, to combine the mechanical grinding, honing, and polishing process with the friction rubbing process by utilizing bonded abrasives, abrasive pads, or a combination of, to achieve the specified level of finished gloss as defined by the CPAA.
- Surface coated concrete - Surface coated concrete does not conform to the definition of polished concrete per the CPAA. It is the operation of applying a film forming coating to a concrete floor surface to achieve a specified level of finished gloss. Durability depends on the quality of the chemical coating used, the amount of traffic across the floor, and floor maintenance.
- Polishing Process - The steps required by a polishing technician to transform the concrete substrate into a specified finished gloss. These steps may include a sequence of grits of bonded abrasives spanning the grinding, honing and polishing stages (ie 70 grit metal bond, 120 grit metal bond, 50 grit hybrid bond, 100 grit hybrid bond, 200 grit resin bond, 400 grit resin bond, 800 grit resin bond, 1500 grit resin bond, 3000 grit resin bond).
- Grinding Stage - The steps of the polishing process that refines the concrete in preparation for the honing stage. This stage is typically the beginning for Class C and D specified floors and may meet the requirements for a level 1 specified gloss. This stage consists of any bonded abrasive that is 100 grit or lower.
- Honing Stage - The steps of the polishing process that refines the concrete in preparation for the polishing stage. This stage can sometimes be the beginning steps for Class B specified floors and may meet the requirements for a level 2 specified gloss. This stage consists of diamond tooling within the 100-400 grit range.
- Polishing Stage - The final stages of the polishing process that refines the concrete to the specified finished gloss levels 3 or 4. This stage consists of diamond tooling that is 800 grit or higher.
- Burnishing - The act of using a high speed burnisher affixed with an abrasive pad to further enhance the microscopic abrasion of the concrete surface to increase the finished gloss.
- Grouting - The act of using a grout that is forced into the pore structure of the concrete substrate to fill surface imperfections.
- Grout - a thin mortar used for filling spaces; also: any of various other materials (as a mixture of cement and water or chemicals that solidify) used for a similar purpose.
- Bonded abrasive - abrasive medium that is held within a bonding that erodes away to expose new abrasive medium as it is used.
- Diamond tooling - Abrasive tools that contain industrial grade diamonds within a bonded matrix (such as metallic, resinous, ceramic, etc) that are attached to rotating heads to refine the concrete substrate.
- Metal bond tooling - Diamond tooling that contains industrial grade diamonds within a metallic bonded matrix that is attached to rotating heads to refine the concrete substrate. These tools are available in levels of soft, medium, and hard metallic matrices that are matched with contrasting concrete substrates. (ie hard matrix/soft concrete, medium matrix/medium concrete, soft matrix/hard concrete) and are typically used in the grinding and early honing stages of the polishing process.
- Resin bond tooling - Diamond tooling that contains industrial grade diamonds within a resinous bonded matrix (poly-phenolic, ester-phenolic, thermoplastic-phenolic) that is attached to rotating heads to refine the concrete substrate. Resin bond tooling does not have the soft/medium/hard characteristics of metal bond tooling and are typically used for the later honing and polishing stages of the polishing process.
- Hybrid tooling - Diamond tooling that combines metal and resinous bonding that has the characteristics of both types of tooling. These type of tools are typically used as either transitional tooling from metal bond tools to resin bond tools or as a first cut tool on smooth concrete surfaces.
- Transition tooling - Diamond tooling that is used to refine the scratch pattern of metal bond tooling prior to the application of resin bond tooling in an effort to extend the life of resin bond tooling and to create a better foundation for the polishing process.
- Abrasive pad - An abrasive pad, resembling a typical floor maintenance burnishing pad, that has the capability of refining the concrete surface on a microscopic level that may or may not contain industrial grade diamonds. These pads are typically used for the the maintenance and/or restoration of previously installed polished concrete flooring.
- Grinder - A multiple head, counter-rotating, walk behind or ride on machine, of various sizes and weights, with diamond tooling affixed to the heads for the purpose of grinding concrete. Excludes janitorial maintenance equipment.
- Burnisher - A variable speed, single or multiple rotating head walk behind or ride on machine that spins an abrasive pad, with or without bonded abrasives, at 1200 rpm or higher.
- Edge polishing - The steps required by a polishing technician to process the concrete substrate along the perimeter of the room(s) to a finished gloss equal to that installed within the open areas of the room. These steps typically involve the same sequence of grits used by the polishing technician within the polishing process and typically are performed within sequence of the grinder.
- Edge detailing - The act of blending or installing a contrasting border along the perimeter of the room(s) using a liquid coating.
- Maximum refinement - The point in time when the diamond tool has refined the surface to the degree to which it no longer cuts or cuts very little under its current weight and variables as defined by the CPAA.
- Pass / Cut - The forward and backward motion with a grinder or burnisher along a grid pattern of the concrete floor required to process the concrete into a specified finished gloss. One pass is typically forward and back within the same pathway, however this may be adjusted by the polishing technician due to the many variables as defined by the CPAA.
- Cross Hatch - a multi-directional pass / cut.
- Variables - An unlimited number of influential changes or pressures imposed upon the polishing technician during the polishing process. (ie weight of the machine, linear speed of the grinder, diamond tooling head pressure, hardness of the concrete substrate, etc)
- Aggregate exposure - Grinding a concrete floor surface with bonded abrasives to
achieve a specified class of exposed aggregate. These are classified as A, B, C and D
with varying levels of exposed aggregate (see Aggregate Exposure Chart)
Aggregate Exposure Chart
CLASS NAME APPROXIMATE SURFACE CUT DEPTH* APPEARANCE A Cream Very little Little aggregate exposure B Fine Aggregate (Salt and Pepper) 1/16 inch Fine aggregate exposure with little or no medium aggregate exposure at random locations C Medium Aggregate 1/8 inch Medium aggregate exposure with little or no large aggregate exposure at random locations D Large Aggregate 1/4 inch Large aggregate exposure with little or no fine aggregate exposure at random locations
*substrate mix design, finish and flatness will affect the appearance.
- Finished Gloss - Processing a concrete floor surface to achieve a specified level of
finished gloss prior to application of any protective treatment; Flat [ground], satin
[honed], semi polished, and highly polished are measured in reflective clarity (DOI), and
reflective sheen (specular gloss). Finished Gloss is classified as levels 1, 2, 3 and 4
with varying degrees of reflective clarity, and sheen. (see Finished Gloss Chart)
Finished Gloss Chart
LEVEL NAME REFLECTIVE CLARITY REFLECTIVE SHEEN SUGGESTED GRIT RANGE SUGGESTED MINIMUM NUMBER OF ABRASIVE PASSES 1 Flat
Flat appearance with no to very slight diffused reflection 10
None to very low 15
Below 100 4 2 Satin
Matte appearance with or without slight diffused reflection Low to medium 100 to 400 5 3 Semi-Polished Objects being reflected are not quite sharp and crisp but can be easily identified Medium to high 800 and higher 6 4 Highly-Polished Objects being reflected are sharp and crisp as would be seen in a mirror-like reflection High to highest 7
- Specular Gloss - A single measurement of gloss by shining a known amount of light at a surface within a specified angle of illumination and quantifying the reflectance. Specified angles of illumination are 20 degrees for gloss ranges higher than 70 GU, 60 degrees for gloss ranges between 10-70 GU, and 85 Degrees for gloss ranges below 10 GU.
- Distinction of Image (DOI) - A measure of how clearly a reflective image will appear in a reflective surface.
- Haze - An optical effect caused by microscopic textures or residue on a surface.
- Rspec - The peak gloss value over a very narrow angle.
- Gloss meter - A device that is capable of measuring specular gloss at 20, 60, or 80 degrees.
- Gloss Measurement - A determination of specular gloss that incorporates distinction of image, haze and Rspec.
- Reflective Clarity - The DOI (distinction of image) value of the degree of sharpness and crispness of the reflection of overhead objects when measured by a device in accordance to ASTM D5767.
- Reflective Sheen - The specular gloss value of the degree of gloss reflected from a surface, at specified angles of illumination, when measured by a device in accordance to ASTM D523-08.
- Surface profile - The advanced measurement of surface topography on a microscopic level of a concrete floor surface with metrology devices.
- Polished Concrete Auditor - A technician that has been trained to test and evaluate a polished concrete surface to ensure that it is within the specified ranges of reflective clarity, reflective sheen, slip coefficient and overall quality.
- Dynamic Coefficient of Friction (DCOF) - The ratio of the horizontal component of force applied to a body required to overcome resistance to movement when the body is already in motion divided by the vertical component of the weight of the body or force applied to the surface where movement occurs.
- Static Coefficient of Friction (SCOF) - The ratio of the horizontal component of force applied to a body that just overcomes the resistance to slipping to the vertical component of the weight of the object or force applied.
- Tribometer - An instrument or device specifically designed to measure the available level of traction upon a floor or walkway surface.
- Mock up - A sample of products and procedures performed at the job site to establish a standard for visual appearance, skill and knowledge level of the craftsman, and overall procedures required to overcome imposed variables and install a polished concrete floor for a particular project.
- Liquid Densifiers - an Aqueous solution of SiO2 dissolved in the respective Hydroxide
(see below) that penetrates into the concrete surface and reacts with the Calcium
Hydroxide to provide a permanent chemical reaction that hardens and densifies the
wear surface of the cementitious portion of the concrete.
- Sodium Silicate
- Potassium Silicate
- Lithium Silicate
- Alkalis solution of Colloidal Silicates or Silica
- The following products do not harden or densify concrete
- Siliconate is a synonym for Sodium Silicate that is a solid without any water and therefore non-reactive in the reactions described above.
- Colloidal Silica SiO2 that is suspended only in H2O is non reactive as a densifier.
- Siliconates are sometimes a truncated descriptions for a Alkyl (organic) Alkali Metal Silicate which are water repellents and react in the acid form of CO2 (Carbon Dioxide) and H2O (Carbonic Acid). These might be used as an additive in Silicate Solutions for early water repelling of the densifiers
- Stain - a pronounced colored spot in the concrete caused by a material which is a soilant, discolorant or a reactant which changes the concrete surface resulting in an undesired appearance.
- Stain - Decorative Application Treatment; The deliberate action of applying a material to the concrete to change the color resulting in a transparent appearance by a chemical reaction, penetrating dye or pigment.
- Stain Resistant - as defined in ASTM D 1308 - Standard Test Method for Effect of Household Chemicals on Clear and Pigmented Organic Finishes.
- Dye - Non film forming soluble colorant dissolved in a carrier designed to penetrate and
alter coloration and appearance of a concrete floor surface without a chemical reaction.
Definition of Sealer from ASTM D16 - a liquid composition to prevent excessive
absorption of finishing coats into porous surfaces; also a composition to prevent
- Sealer-Semi Impregnating Stain Protection - a film forming material which will penetrate into the polished and densified concrete leaving a protective surface film of less than 0.5mils which meets the OSHA requirements for slip resistance as tested by ASTM D 20471, and Stain resistance of ASTM D 13082.
- Sealer-Impregnating Stain Protection - Non film forming stain and food resistant penetrating sealer designed to be applied to densified and polished concrete. Material must meet the requirements of OSHA for slip resistance as tested by ASTM D 20471, and Stain resistance of ASTM D 13082.
- ASTM D2047 - Standard Test Method for Static Coefficient of Friction of Polish-Coated Flooring Surfaces as Measured by the James Machine.
- ASTM D1308 - Standard Test Method for Effect of Household Chemicals on Clear and Pigmented Organic Finishes
- Film Forming Coating - a film forming material which is designed to be a surface coating
on concrete with a minimal film thickness of greater than 0.05 mils. which meets the
OSHA requirements for slip resistance as tested by ASTM D2047 and stain resistance
of ASTM D1308.
- Typical Film Formers
- Methyl Methacrylates
- or other film formers compatible with concrete
- Pigmented Microstains - Fine pigment particles (<3.9 x 10- -4 inches) suspended in water-based silicate solution that penetrates concrete and reacts with calcium hydroxide to lock in color particles.
- Edge Treatment - A liquid clear or pigmented coating that is applied to any concrete-tovertical surface to define the edges.
- Joint Filler - Compressible material used to fill a joint to prevent the infiltration of debris and provide support for sealants applied to the exposed surface.
- Repair Material - A product that is designed to repair cracks and surface imperfections. The specified material must have sufficient bonding capabilities to adhere after the polishing to the concrete surface and provide abrasion resistance equal to or greater than the surrounding concrete substrate.
- Processing - The act of changing a concrete floor surface by means of a multi-step mechanical operation that involves cutting and/or refining the surface to the maximum potential with a bonded abrasive where each step cuts progressively finer microscopic peaks and valleys. Each step must be refined to its maximum potential in which the abrasive no longer cuts or cuts very little under its current weight and set variables.