The Romans made concrete that has lasted for centuries but how long does modern day concrete compare? Here in Tucson there are a lot of variables that can affect the life span of your concrete. Here are just a few:
Mix design – Modern day concrete contains many chemicals. From accelerators to retarders and everything in between the original design has long since left the scene. I have to say, from what I have seen… The Romans had a better product.
Installation – This is the factor that most affects the longevity of your concrete. If your slab is poured too thin and without a sufficient number of control joints it is doomed to fail. Just ½” of depth can be the difference between a successful endeavor or sending your driveway to the landfill long before it’s time.
Concrete psi – Concrete is considered a 30 year product. I’ve seen it last longer and I’ve seen it fail early. The psi plays a big role in longevity. A The higher the psi is, the lower the permeability of your concrete will be. The tighter surface will keep out the moisture. Time tends to raise less havoc on a 4000 psi mix than a 3000. See our post on concrete psi to learn more.
Coatings – If you coat your concrete coating it is protected from the elements for a time.. Unfortunately as the coating ages it allows moisture in. Once the coating is compromised moisture makes it’s way in quickly but escapes very slowly. This seems to shorten the overall life of your exterior concrete. It deteriorates the surface making it much more difficult to re-coat.
Nothing is forever but Concrete lasts longer than most. As a rule of thumb I’d say modern concrete lasts for 20-50 years. If you have questions about your concrete project please let us know. Send your questions to bstconcretellc@gmail.com