Concrete is an amazing product. It has been used for centuries with its origins dating back to around 300 BC. C. Although there are reports that the use of concrete preceded that time, the first to use concrete effectively were the Romans. Ancient Rome had an abundance of ash, lime and water, the key ingredients. The ancient master builders built cities and as a result an advanced culture. It could easily be argued that without concrete we would still be living in tents. Human beings would not have progressed to where we are today.
However, concrete is not without flaws. The garage floor is a perfect example. Many houses were built with spancrete. Spancrete are precast concrete panels that are typically 24 feet long, 3 feet wide, and 6 inches thick. They are placed on the foundation of a house above the basement. Concrete is then poured on top about 4 inches thick. The problem is that this top layer of concrete cracks as it sits right where the spancrete panels abut each other. In the main part of the house this is not a problem, but it is a problem in the garage.
There are some forces at work that are a headache for a homeowner. First, let’s start with a crack in the concrete floor of the garage. When a car drives in with snow or rain dripping onto the surface, it works its way into the crack along with deicing salts. The salts quickly eat into the concrete, causing decomposition. If there is spancrete underneath, the water will fall into the basement. The result is a damp, moldy and unhealthy space. If the concrete is level, the water will run down the crack and work its way under the slab. Once it freezes it lifts the slab up and then backs up when it thaws. This constant movement is not good.
Many attempts have been made over the years to create coating products and systems that combat this problem. Like everything in construction, there are right and wrong solutions. The first obvious solution is to fill in the cracks inherent in each concrete garage floor. What you don’t see, however, is that the walls of the crack are probably damp. The reason is that concrete is porous. Surface water drips into the crack and moisture vapor if your slab is level will push up. The only crack filler that works is a polyurea that will dry below the surface. The polyurea must be fluid enough to flow to the bottom of the crack and fill the void all the way to the surface. The wrong stuffing will never dry out and will stay musky and moist forever. Unless this critical step is done correctly, it will never solve the problem.
Liners are the logical topical solution but very few work. Unless the garage floor is properly prepared and an expensive epoxy is applied, it risks delamination. You may have seen chipped and delaminated epoxy coatings. Sometimes they are applied incorrectly or are not of high quality. With all the factors at play that can cause problems, only the highest quality stands a chance.
Advanced technology polyurea and polyaspartic products have been developed in recent years that can handle the harshest conditions. However, not all mixes are created equal and not all applicators have the necessary knowledge or equipment to handle these exotic high-performance mixes.
The proper process is to grind the concrete surface removing all possible bond breakers and opening the surface pores. The new Pure Bred products will actually soak into the top layer of the concrete and set when dry. This makes the coating part of the concrete instead of just adhering to the surface.
As the coatings are applied, usually a total of 3-4 coats, with anti-slip particles added to each coat, a highly durable surface is created. Even floors that seem hopeless can be restored to showroom condition and will perform for the long haul. They are not just the right polyureas, but those that are in the hands of a professional. Of course, who really qualifies as a seasoned professional and how do you know he’s hired the right one? That is for another article.