Correctly estimating the thickness needed to get the job done right is one of the biggest issues a contractor faces when applying a polishable overlay, says David Stephenson, president of American Concrete Concepts in Springdale, Ark., who has been working with them for six or seven years.
If you think you'll only need a 1/4-inch overlay and it ends up being a half-inch, your cost has doubled and your headache has just begun. "A polishable overlay is very expensive, " Stephenson says. "When you bid on an overlay project, it's very important to know how much material to purchase. " Too much and you'll end up with a lot of extra product. Too little and you're out of luck. "Once you get going on the job, you have to have it all there to finish it out. You can't stop and go get more. "