One thing that I don't think has been mentioned here before:
Not all epoxy floors are the same. We have discussed basic water-based and solvent-based epoxy floors in this thread, but those are generally NOT the type of floors that are installed in most heavy-duty shops, such as the Nascar shops mentioned earlier. A typical epoxy "coating" floor that is usually rolled on is nothing more than multiple layers of a liquid material of some sort. The most durable form of epoxy floor is not a "coating", BUT an epoxy/aggregate or slurry-filled floor. The epoxy that is used in these types of floors are nothing more than a "binder" for the part of the floor that makes it durable, which is the ceramic sand or silca filler. When a ceramic or silica slurry filler is used in conjuntion with a 100% solids epoxy, it becomes very dense, and very impact resistent. Without the filler, it is nothing more than a low-duty coating. These types of floors are usually 3/8" to 3/4" thick, and are troweled onto the floor, not rolled.
Here's an example of how a filler works in another type of product:
Concrete is primarily composed of three components...Sand, Rock, and cement powder. The cement is nothing more than a "binder" to bond the sand and aggregate together. Without the sand and aggregate, cement by itself is not very durable and will not absorb impacts or heavy weight loads. Try calling your local concrete batch plant next time you are pouring concrete and them that you want to delete the sand and rock from the mix, and they will tell you to go fly a kite. Cement is just a portion of the complete concrete mix, and cannot be used alone.
Although epoxy does have some durable characteristics, it is much like the cement in concrete and must have a binder added to it to be strong. With this binder added to epoxy, it is also much less suseptable to moisture, and generally when it is damaged, it is not a complete break through of the covering into the substrate because of the thickness. The impact and durability factors of an aggregate filled epoxy system are 10 times that of a simple solvent-based epoxy coating system. This is why Health departments in Calif. only authorize aggregate filled epoxy floor systems in the kitchen areas of restaurants, but do NOT approve simple epoxy floor "coatings".
Almost all new concrete floors that are intended to have a floor covering placed over the top of them (whether it is epoxy, carpet, wood, etc.) also have a vapor barrier such as thick plastic sheeting placed under the concrete slab prior to pouring concrete. When a new house foundation is being poured, this vapor barrier is installed prior to concrete placement, but contractors generally DO NOT place this sheeting under garage foundations. That is why you will find moisture escaping in the garage and not in the house. If you have found moisture escaping in the house and the contractor did not place a vapor barrier, you have a good lawsuit on your hands!
Oh,... and the average cost of an aggregate filled epoxy system is roughly twice to three times that of a non aggregate filled epoxy system. But,...once again, you get what you pay for!
Just a little food for thought for you guys who have or are about to put down that do-it-yourself epoxy floor in your garage.
