Not all concrete floors are perfect for polishing, in fact some existing concrete surfaces will not generate the strength and high sheen exposed aggregate finish that the business owner or homeowner visualized or anticipated. Most homeowners see flooring with a high gloss sealer on ground concrete substrate and presume that this is polished concrete; however this is not always the case. Those in the concrete industry know these applications as grind and seal.
Polished concrete is not sealed. When polished concrete flooring is taken up to the higher grit levels and has been densified (this flooring minus the densification step will be much more subject to dusting, staining and abrasion) the floor will deliver a high gloss appearance that is comparatively stain resistant for a concrete floor without any form of sealer. Polished concrete floors are not stain resistant as so many people think they are.
Grind and seal floors are precisely as the name implies; the substrate is ground back, normally to the 200 to 400 grit level, then covered with a topical concrete coating. These coatings or sealers are usually epoxy or polyurethane.
Some of the advantages of a grind and seal over polished concrete are:
- Cost effective (often one third of the price).
- Greater abrasion resistance (dependent on the sealer used).
- Much less labor intensive.
- An entirely non-porous surface (will not harbor bacteria).
- Low maintenance.
If you are looking for a polished concrete floor, you should be mindful of these different applications. Questioning your contractor on their techniques and processes is important. Understanding which products they use for a grind and seal floor is vital. Not all sealers are produced equally and the lesser quality sealers will certainly yellow and blush or even flake and peel over time.
Far too frequently the hopes of polished concrete floors are not met or the floor deteriorates over a brief period of time. Buying polished concrete flooring systems and receiving a grind and seal is a commonplace occurrence. Selling a polished concrete floor and not proposing the benefit of the densification process while still charging top dollar is also a regular incident.
Knowing a few of the methods and the differences in the procedures, which have a similar look to the inexperienced eye, is important to both the owner of the floors and also to the reputation of the concrete flooring industry.
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