The Truth about Preparation, Primers and Warranty in the DIY Garage Coating Market
In the past 20 years, resinous coating products (epoxy) formerly used in manufacturing plants have shifted to greater DIY use. The DIY garage floor coating market is filled with very good information coupled with much misinformation. The goal of a manufacturer is to sell a product. Product sales are directly tied to ease of application and cost. When the application becomes too complex, buyers reject. When the cost per square foot rises too high, buyers reject. Therefore, the goal for manufacturers is to make the process “easy” and the cost “affordable”. Unfortunately, easy and affordable can limit the lifetime expectancy of the coating system.
The truth is “acid etching” is a recommended surface preparation method. It is recommended if you can’t perform mechanical abrading methods such as “diamond grinding” or “shot-blasting”. Acid-etching does not address “laitance”. Laitance is weakness in the surface of the substrate. Laitance is caused by too much water, freezing and/or excessive trowel work. Laitance, typically, does not present itself until you apply an epoxy floor coating system on it. This is not a good time to find out you have laitance. The availability of hand-held diamond grinding wheels, smaller diamond grinding machines, brush style grinders and dust control systems should help eliminate acid-etching as the main method of floor preparation. However, it is still offered by many manufacturers as it is “easy” and costs “less”.
Many quality garage coating kits include a 100% solids epoxy. 100% solids epoxy makes an excellent base/intermediate coat. It hides imperfections, has good initial gloss and is a great vehicle for chips, quartz and color granules. However, there are (2) Achilles heals to this product. 100% solids epoxy does not penetrate well. This lack of penetration into the substrate can cause issues later in the lifetime of the product. Secondly, it is so thick that air can become trapped in and cause “volcanoes” or “bumps”. The air can be from a porous surface (epoxy displaces air in pores, air releases and becomes trapped in coating). Primers are thin and therefore can penetrate the surface deeply giving the base or intermediate coat a robust lock to the substrate. Primers are thin and therefore when they displace air in a porous surface, the air can escape through the coating without leaving a “volcano” or “bump” on the surface. In addition, primers encourage uniformity in subsequent coats and extend the coverage rates especially over porous substrates.
Fact is after selling millions of gallons of product, the coating manufacturer knows when they have a problem with a product almost immediately. Batches are tested before packaging. Tests are recorded and wet samples are kept for one year for further testing if required. If the product catalyzes and becomes hard the coating manufacturer did their job. Bumps, volcanoes, peeling, lifting, hot-tire issues can all be routed back to preparation or application. It is extremely rare that a coating manufacturer ever pays for a warranty claim and/or supplies more product based on a customer calling in with a warranty claim. Consumers should concentrate more upon the quality and responsiveness of the manufacturer’s customer service and less on warranty. Good customer service and knowledge is worth its weight in gold!
In summary, a long lasting and attractive garage floor system should include a mechanical preparation process, penetrating primer and a protective clear coat (urethane or polyaspartic). These items add more cost but help to eliminate risk in the application process and greatly extend the overall lifetime of the flooring system.