The Best CSP for Your Concrete Coating
Discover how CSP for coatings is applied and which coating types work best depending on the concrete’s “complexion.”
- The coating you use on your floor will depend on its roughness
- Smoother surfaces can take thinner coatings
- Rougher surfaces need a thicker coating
- Identifying the best coating to meet your needs ensures you’re happy with the finished product
Our learning center contains many blogs and podcasts packed with expert advice on concrete coatings. It’s all in there, from explaining the differences between epoxy and urethane to settling the sealers vs. guards confusion and debate. In fact, it’s a great idea to absorb both of those before you read this!
Today’s deposit in the knowledge bank deals with one of the most important metrics in the trade: the concrete surface profile (CSP) of a floor. This essential piece of data helps contractors select the right kind of coating for the slab. Here’s how it all works.
How CSP for coatings creates a sticky situation (in a good way)
Concrete coatings wouldn’t be of much use if they didn’t adhere to the substrate. The only way they can do that is if the coating and the concrete are a good match – or, to be more illustrative, when the concrete’s complexion matches the makeup. Go with us on this one.
CSPs are standardized measures ranging from 1 to 10, per the ratings set by the International Concrete Repair Institute (ICRI). The smoothest concrete surfaces are rated from 1 on up to the 10s, which are – you guessed it – the roughest. CSP 10 is the most recent rating, having been added in 2013.
Once onsite, concrete contractors can whip out their handy ICRI chip set – ten little surface samples that can be compared with the slab to match it with the correct CSP. It’s kind of like taking a swatch to the hardware store to find the right tint of paint. Once the match is made, a coating can be chosen that will bond successfully with the substrate.
How CSP for coatings connects to finishes
Here’s a closer look at the ten ICRI surface classifications, the methods contractors can use to achieve these gradings, and which finishes work best with them. Remember that a “mil” is a tiny measurement of only one-thousandth of an inch. When we convert that into millimeters, we’ll use “mm.”
These can be prepped using acid etching, grinding, low-pressure water, or detergent scrubbing. It can be coated with sealers like low-viscosity epoxy and urethane or acrylic. Sealer thicknesses typically range from 0–3 mils (0.075 mm) or a thin film of 4–10 mils (0.1–0.25 mm).
These can also be prepared by grinding or acid etching. Coatings can be thin-film sealers between 4 and 10 mils, with low-viscosity primers recommended. These are a good solution if surfaces won’t be handling too much foot and equipment traffic.
The thinnest sealers only go so far on these brush-blasted slabs – 4–10 mils or high build coatings from 10–40 mils (0.25–1 mm) may be required. Some contractors might go to 60 mils (1.524 mm) or above.
Abrasive sand blasting or shot blasting may be prioritized for prep work over acid etching or grinding. CSP 3 and upward are better for sites where surfaces face an increased risk of heavy abrasions or spills.
Medium shot blasting creates this surface rating with light scarification – a controlled process where spinning blades fixed to a drum create chips in the slab. Thicker coatings like urethane or epoxy are called for, like high builds in the 10–40 mils range or self-leveling ones in the 50 mils to one-eighth of an inch (1.25–3.175 mm) bracket.
A scarified and medium shot blasted surface. Urethane and epoxy with aggregate are good coating matches in high build or self-leveling thicknesses. Polymers measuring one-eighth to a quarter of an inch deep (3.175–6.35 mm) are sometimes applied.
-CSP 6 and CSP 7
Heavily shot blasted surfaces that will need the thickest overlays and coatings (self-leveling or polymer overlays).
We’re up into the highest roughness ratings now, which require the thickest overlays and may sometimes also need a concrete coating or another kind of repair coating. These will measure in the quarter-inch category.
-CSP 9 and CSP 10
Heavily scarified concrete surfaces with heavy-duty preparation methods like flame blasting, super-high pressure water blasts, or milling/rotomilling. Only the thickest coatings will adhere, and some repair work may be necessary on the concrete as part of the process.
You’ve got to pick the perfect surface prep
Selecting the most effective surface preparation process is critical. Some approaches, such as acid etching, are good for removing laitance but can be tough to neutralize and, being acidic, may be harmful to anything in the immediate vicinity. A very well-ventilated space is also necessary if acid is used.
Other prep methods like milling, grinding, or scarifying could cause microcracks in the concrete. These super small splits can’t be left as is because they can weaken both a slab’s compressive strength and the aggregate/mortar bond. They must be repaired as the contractor works.
The thing is, microcracks aren’t visible to the naked eye. “How do contractors fix what they can’t even see?” you may ask. This can be achieved by adding a reactive treatment that blends with the dust from the grinding process and fills in microcracks automatically.
Your takeaway on CSP for coatings
The right choice of coating is all that stands between concrete and a significantly shortened lifespan (for the slab, that is – your lifespan will be fine). A coating that’s too thin will have to be repaired sooner rather than later, bumping up your expenses and possibly halting your business processes while repair work takes place.
Contact the pros at Concreate, and our experienced team will put down the right coating the first time, or professionally remove an old one that’s not doing the job. We can also help you with concrete repairs and many other services, so don’t hesitate to reach out and ask any questions!