Perfect CC Midwest Inc provides Illinois, Wisconsin, Indiana, Iowa & Michigan with the highest quality Polished Concrete Flooring Installation. While many contractors may simply try to provide a generic polished concrete per request, we educate the buyer as what is possible due to their current flooring conditions. Not all finish types of polished concrete will be available per current concrete condition. Utilize the chart below for a better understanding of what end results for your surface may be. Click Here for an Immediate Consultation and Proposal
The Stages of Mechanically Diamond Polishing Concrete
Correctly concrete polishing a concrete floor requires three main stages; Grinding, Honing and Polishing. The grinding stage is to remove surface obscenities such as prior topical flooring materials such as mortars from tile, glues from laminate or vct, or even old sealers and epoxies. The grinding process also exposes the desired aggregate appearance in the concrete surface- grinding deeper expose more stone, less more fine sands remain visual. Note, the natural placement of concrete will always cause uneven exposure appearances. For example, heavier stone is likely to be more immediate around joints due to curling during the concrete curing. The honing stage is the intermediate part of the concrete polishing process that uses finer diamond abrasives to remove the visual scratch pattern left from the initial heavy grinding. Honing is typically performed in three to four different sequential passes until the scratches are no longer visual from a standing point of view. Once all visual scratches are removed from the concrete floor, the concrete polishing fine diamonds can proceed. The final steps of concrete polishing are than performed, again with three to four sequential fine abrasives to create a matte to high gloss polished concrete appearance. The amount of passes will dictate the final gloss level of the surface; per request from the specifier.
Wet Concrete Polishing Vs. Dry Concrete Polishing
While concrete polishing can be performed with fully wet or dry concrete polishing systems, there are many pro’s and con’s to each system. Perfect CC Midwest has perfected a proprietary hybrid system using both concrete polishing in the wet and dry process during our installations. Our hybrid system allows the highest refinement possible for a polished concrete floor which is the most important factor when considering longevity in the final polished concrete surface.
Wet Concrete Polishing Benefits
- Higher Level of Refinement means high final gloss, longer life span of polished concrete surface.
- Dust free concrete polishing process.
- Efficiency of tooling made for wet concrete polishing reduces tool consumption- less materials used.
- Water lubrication of tools make for quicker mechanical polishing of concrete due to the cooling of the diamond tools in the process.
Dry Concrete Polishing Benefits
- Easier method to perform for inexperienced concrete polishing companies.
- Less equipment needed for the entire concrete polishing process.
- Less messy for inexperienced concrete polishing companies.
- Dry concrete polishing is easier to perform in small, detailed spaces due to reduced cleanup.
Wet Concrete Polishing Cons
- More equipment required to aid in retrieval of concrete slurry from concrete grinding and polishing processes.
- Necessity to properly dispose of concrete slurry made in the concrete polishing process. The polished concrete slurry cannot go down wastewater drains!
- Extra preliminary precautions must be taken to protect work area and workers’ i.e. covering drywall with plastic, wrapping 480v powered cable connections.
- Inexperienced concrete polishing companies can be overwhelmed by the slurry created and leave an unimaginable mess.
Dry Concrete Polishing Cons
- Less refinement of the concrete due to the abrasive nature of dry concrete grinding.
- Dangerous silica dust in the air during the concrete polishing and grinding processes- inexperienced concrete polishing companies may not have the sufficient dust extraction units to meet the demands of the concrete grinding dust.
- A fine layer of dust on lighting, electronics or devices that naturally grab particles.
Typical errors inexperienced concrete polishing companies make and how they affect longevity....
Whether new to the concrete polishing trade or rushing a low bid project to salvage profits, the following are unfortunate ‘shortcuts’ lackluster concrete polishing companies are making on their clients floors- without the clients’ knowledge let alone their acceptance of how it will greatly reduce the longevity of the polished concrete floor:
- Doing only enough honing to remove the visual scratches, than applying a glossy sealer to mimick the natural look of actually mechanically polishing the concrete. While visually acceptable, the reality is the glossy sealed polished concrete appearance will only last as long as the sealer placed atop as the concrete below is not polished. This can reduce the floors’ life of gloss literally from years to months.
- Not densifiying the slab sufficiently or even applying a chemical hardener at all. Concrete densifying is a chemical applied to the concrete at certain stages of the polished concrete process to harden and dustproof the concrete that has been preground. Not only does densifying the concrete slab create a tighter, finer polished concrete finish post all polished concrete stages- it aids in keeping the concrete’s durable, dust free surface for years to come.
- Not densifying sufficiently, knowing which densifier type to use or even when to apply the densifier. Simply smearing a swipe of densifier on the to be polished concrete is not enough product for the chemical changes in the concrete floor surface to take place. Using the wrong densification type depending on the slabs condition or point in the concrete polishing process will also greatly affect the densifiers performance.
- Running machine across the floor with the concrete polishing diamonds as fast as operator can move! A typical concrete polishing process may involve running 6-7 different abrasives across the concrete floor in sequential passes. The walking speed of the operator is key in being sure to fully refine the polished concrete floor to it’s full final polished concrete potential. Many companies rush the passes which while the lackluster final appearance should even be obvious to an unsuspecting client- they are able to ‘cheat’ the look and hide it with a glossy sealer. Again, taking a decades long floor and reducing it to months of yield.
- Incorrectly patching methods and or materials…Epoxy mortars are highly adhesive in sticking to cracks, spalls in the concrete. They create a tight, rigid bond and can be polished with the rest of the concrete surface when the correct aggregate additives are used. Cementitious patching compounds should not be used for shallow spalls as they will easily pop out over a short period of time as they do not have the adherence capabilities comparable to epoxy mortars. Attention needs to be put to the cementitious required depth of installation- these materials are to be used for larger repairs whereas the epoxy mortars in those very large repairs may tend to smear during the polishing process.
- Filing Joints with rigid fillers rather than two part, flexible polyurea. Joints are in the concrete floor for a reason- giving the cracking somewhere to go. By filling the joints with rigid epoxy mortar materials or even worse, cementitious repair materials- any future movement in those joints will now be pushed outside the joint causing visual cracking along the joints themselves. Two part, flexible polyurea cures to a hard rubber like consistency and is ground and polished with the rest of the concrete floor. These correctly done joint repairs give the floor a nice seamless appearance while maintaining the true function the joint is meant to have.
- Incorrectly choosing diamonds abrasives- the initial cutting diamonds known as metals if not correct grit or hardness will not achieve the correct depth of cut to expose the client requested aggregate appearance or even be able to fully remove all mastics or other floor covering materials. The poor performance concrete polished may simply pass this off to the client as ‘that’s all we could do’ while in reality the correct tool was not fully used. Also, in the final stages of concrete polishing, using cheap resin filled polishing segments that actually transfer resin to the floors’ surface rather than actually mechanically diamond polish the concrete. This creates a false, gummy like shine on the concrete whereas again, if not monitored- can be hidden below the further glossy sealer without the clients’ knowledge until the floor shows a yellowing, amber like shine months later.
Polished Concrete Imperfections
While quality concrete polishing contractors put every effort into mechanically grinding and diamond polishing the concrete floor, the natural characteristics of the concrete itself can often times remain even after the concrete grinding and diamond polishing takes place. Often these imperfections are known as ‘character’ and many concrete polishing purchasers are happy with the variances these discrepancies give the overall finish. How drastic some of these visual imperfections may be relies on how the actual concrete was originally poured and the actual cement material used.
Concrete slabs are poured and manipulated into place by concrete flatwork contractors. Simply put, ground work is put into creating a hard pact ground base (typically gravel) than the fluid cement material is placed on top. How much time is spent creating a flat, smooth surface will dictate the final visual appearance when a concrete polishing contractor grinds that slab. Be it 1 month post new concrete pouring, or even forty years after- imperfections in the slab may still be apparent if the depth of the visual deficiencies goes below the surface. Many times; underlying visual aspects may be below the top of the concrete, only to forty years later be exposed after grinding and polishing the concrete floor. For example; boot prints or rake marks. If the concrete pouring contractor was rushing the raking of the fluid concrete because it was an overly hot day, the concrete hardens faster- the rake marks can often times show up in the form of lines of stone (when ground to expose the stone). This is because, even though the concrete pouring contractor was able to smooth the surface of the cement, the rapid drying concrete did not have the remaining fluidity for the stones to evenly settle. There are endless visual discrepancies that can occur directly related to the when and how the concrete was poured. No matter how talented a professional concrete polishing contractor maybe, many of these discrepancies will not be able to be removed. In example, the rake marks will typically be the full depth of the 4″ concrete slab; a heavy full aggregate ground and polished concrete floor removes 1/2″ of cement while most average, non specified aggregate appearances only remove 1/8″. It should also be mentioned, in the same scenario that the concrete pour was too quickly placed or attention to grading was not put forth; the aggregate (stone within the concrete floor) will sit very unevenly. Meaning, if the concrete polishing purchaser wants no large aggregate, just a simple fine sand appearance (salt & pepper polished concrete)- even after a light grind there will be random sections that show large stones in the polished concrete. This is especially routine on cold joints, or pour stops (where sections were poured in phases) due to curling of the concrete slab during initial curing.