Concrete floor coating systems are frequently specified to be textured to improve traction. The surface texture, however, is only one variable that affects the slip resistance of a surface. Slipping can arise from a failure of traction on the interface between, for example, the footwear and the walking surface and is affected by the floor surface, contaminants on the floor, the quality of footwear, and gait dynamics. Almost all slips and falls occur on wet or contaminated (lubricated) floors. Until recently there was no industry standard that facility owners, specifiers, or installers could reference for the degree of surface texture desired.
SSPC: The Society for Protective Coatings issued a new standard on November 1, 2018, “Concrete Coating Texture Standard” (SSPC-CTS 1) that classifies concrete coating finish textures applied to flooring systems. The primary objective of the standard is to provide qualitative and quantitative language to describe the texture finish of concrete floor coatings.
There are several factors that influence the Coating Texture Finish, including the profile of the substrate to be coated (especially for thin film applications), the coating material (resin), the aggregates incorporated within the coating material or applied during application, the methods used to apply the coating and aggregate, and in some cases the environment during application.
SSPC-CTS 1 establishes a classification system for the textures of finish coats in concrete flooring systems. When used in conjunction with a set of tactile comparators (described later), it establishes a standard terminology that can be used by owners, specifiers, and concrete flooring installers to manage the expectations of all parties regarding the surface texture. Note that the standard is not a slip resistance guide, nor does it assign a definitive slip resistance Coefficient of Friction to any texture finishes.
SSPC-CTS 1 classifies four Coating Finish Textures (CFT) based on a qualitative description and quantitative average finish texture peak height in mils and micrometers.
Coating Finish Texture “A” (CFT-A) provides a slight surface texture that results from the physical properties of the resin, an underlying texture of the substrate, a flat (flake) aggregate, or a fine aggregate contained within the coating. The measured texture ranges from 2 to 6 mils (50 to 165 micrometers).
Coating Finish Texture “B” (CFT-B) exhibits a heavier texture resulting from a thixotropic resin and/or finer mesh aggregate that is either rounded or angular in nature. The measured texture ranges from 7 to 18 mils (166 to 465 micrometers).
Coating Finish Texture “C” (CFT-C) is designed to provide more aggressive texture, especially for wet environments, and are frequently designed with sub-rounded or angular aggregates. The measured texture ranges from 19 to 30 mils (466 to 775 micrometers).
Coating Finish Texture “D” (CFT-D) is designed for environments requiring aggressive texture (created by incorporating large angular aggregate), where deposition of heavy contamination between cleanings is expected. The measured texture ranges from 31 to 50 mils (776 to 1270 micrometers).
Coating Finish Texture Greater than “D” (>CFT-D) is used to classify textures for extreme conditions and are typically used in specialty applications. The measured texture is greater than 50 mils (1270 micrometers).
To assist the communication process for new specifications and installations, SSPC-CTS 1 references a series of tactile texture comparator coupons (available from SSPC) that can be used as visual and tactile representations of the desired texture (Figure 1). Eight distinct textures are represented on comparator coupons corresponding to the classifications defined in the standard. Each coupon illustrates the variability within each designation depending on the aggregate shape (rounded or angular):
CFT A: Mid-range (2-6 mil) texture using rounded aggregate (or stipple finish)
CFT A: Mid-range (2-6 mil) texture using angular aggregate
CFT B: Mid-range (7-18 mil) texture using rounded aggregate
CFT B: Mid-range (7-18 mil) texture using angular aggregate
CFT C: Mid-range (19-30 mil) texture using rounded aggregate
CFT C: Mid-range (19-30 mil) texture using angular aggregate
CFT D: Mid-range (31-50 mil) texture using rounded aggregate
CFT D: Mid-range (31-50 mil) texture using angular aggregate
These benchmark texture designations may be referenced in specifications, product data sheets, application guidelines, and contract documents to effectively communicate the desired finished texture. Also, since textured surfaces are frequently wear-surfaces, these coupons can assist facility owners and maintenance staff in determining when an area may require cleaning or renewed application of finish texture.
Alternatively, one manufacturer (DeFelsko Corporation) produces an instrument and special remote probe designed to measure the coating finish texture up to 60 mils (Figure 2).
In summary, SSPC CTS-1 Concrete Coating Texture Standard provides the concrete floor coating industry with standard terminology and several levels of coating finish textures that can be used by facility owners, specifiers, and installers. It is complemented with a set of tactile texture comparator coupons that can be used to communicate the desired finished texture.