The Concrete Garage Floor
Concrete is an amazing product. It has been used for centuries with it’s origins dating back to around 300 B.C. Though 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 an advanced culture as a result. It could be easily argued that without concrete we’d still be living in tents. Humans would not have progressed to where we are today.
However concrete is not without it’s flaws. The garage floor is a perfect example. Many homes were built with spancrete. Spancrete are precast concrete panels that are typically 24 feet long, 3 feet wide and 6 inches thick. They are laid on top of a home foundation over the basement. Then concrete is poured on top about 4 inches thick. The problem is that this top layer of concrete cracks from settling right over where the spancrete panels abut each other. In the main part of the home this is not an issue, but is a problem in the garage.
There are a few forces at work that are a headache for the a home owner. First let’s start with a crack in the concrete garage floor. When a car drives in with snow or rain dripping on the surface it works it’s way into the crack along with de-icing salts. The salts rapidly eat into the concrete which causes decay. If there is a spancrete underneath water will drip into the basement. The result is a wet, moldy unhealthy space. If the concrete is on grade, water will go down the crack and work it’s way under the slab. Once it freezes it lifts the slab, then recedes when it thaws. This constant movement is not good.
Many attempts have been made over the years to create coating products and systems that will combat this issue. Like with everything in construction, there are right and wrong solutions. The first obvious solutions is to fill the cracks inherent in every concrete garage floor. However, what you don’t see is that the walls of the crack are probably damp. The reason is that concrete is porous. Surface water drips down into the crack and moisture vapor if your slab is on grade will push upwards. The only crack filler that works is a polyurea which will dry below the surface. The polyurea needs to be fluid enough to flow to the bottom of the crack and fill the entire void to the surface. The wrong filler will never dry and will remain mushy and wet forever. Unless this critical step is done right it will never solve the problem.
Coatings are the logical topical solution but very few work. Unless the garage floor is properly prepped and an expensive epoxy applied you run the risk of delamination. You may have seen chipping and delaminating epoxy coatings. Sometimes they are improperly applied or not high quality. With all the factors at work that can cause problems only the highest quality stand a chance.
In recent years advanced technology polyurea and polyaspartic products have been developed that can handle the harshest conditions. However not all blends are the same and not every applicator has the necessary knowledge or equipment to handle these high performance exotic blends.
The proper process is to grind the concrete surface removing all potential bond breakers and opening up the pores of the surface. The new Pure Bred products will actually absorb into the top layer of the concrete and lock in when they dry. This makes the coating part of the concrete rather than just stuck to the surface.
As the coatings are applied, typically a total of 3-4 coats, with non-slip particles added to each layer a highly durable surface is created. Even floors that look like they have no hope can be restored to showroom condition and will perform over the long term. It’s not just the right polyureas, but those in the hands of a professional. Of course who really qualifies as an experienced professional and how do you know you’ve hired the right one? That’s for another article.
