One of the world’s most durable construction materials, concrete can stand up to considerable punishment. That said, newly placed concrete can be very sensitive. If you don’t give a fresh concrete surface time to dry and cure, it can quickly warp or crack. Read on to learn how long it takes for new concrete to fully harden.
Concrete is a composite material composed of coarse and fine aggregate which is bonded together with fluid cement that becomes very hard over time.
Contrary to popular belief, cement and concrete are not the same things. A typical concrete surface is made up of three basic components: aggregate (sand, rock or gravel), ordinary water and Portland cement. The cement acts as a binding agent when mixed with aggregates and water. This mixture is poured and leveled, ultimately hardening into the durable material used in so many construction projects.
While concrete can appear to dry in a matter of hours or days, it won’t fully harden or “cure” for quite a while. Concrete usually takes about 28 to 30 days per one inch of slab thickness to harden to 85-90% relative humidity. Even after that, concrete will continue to further harden for a significant amount of time.
Although it only takes about 28 days to cure concrete, the curing process can take months, because excess water still needs to evaporate. The general rule of thumb is that it takes about 28 to 30 days to dry for each one inch of slab thickness as long as the conditions are right. This means you need a consistently warm temperature and low ambient relative humidity.
There are several key factors that can slow down or speed up the drying time for concrete. These include:
Humidity and Temperature: Exterior temperature and humidity play a very important role in the curing and drying process. Concrete will dry and cure faster in high temperatures and slower in colder weather. Quicker dry and cure rates make spring through early fall the ideal times for pouring concrete.
Moisture Content: If concrete has high water content, it will take much longer to cure than concrete with lower water content. Experienced concrete professionals know how to add the appropriate amount of water for drying that's not too fast or too slow.
Concrete Type: Different concrete mixtures have varying curing and drying rates. Industrial concrete mixes tend to take longer than quick-dry concrete mixes that use less water.
Because concrete continues to harden for months after it’s poured, there’s no way to say when it will fully cure. The real question is: how long will it take for a new concrete surface to cure well enough for whatever purposes it is designed for? For instance, how long before you can walk or drive on it without causing damage?
While there are some key factors that can add or subtract a few hours from drying and curing time, most properly poured concrete can handle foot traffic after 24 hours and vehicle traffic after 48 hours. You can usually treat a new concrete surface as “fully hardened” with most expected max weights at about 30 days after the pour.
Concrete isn't a simple pour-it-and-forget-it process. It requires years of experience and expertise to ensure an attractive, reliable surface that will stand the test of time. If it’s poorly formulated or improperly poured, a new concrete surface can fail in a short amount of time. This is why it’s so important to work with a reputable provider with a strong reputation for serving residential and business clients in the local community.
With decades of experience, Enright can take on any type of concrete project, small or large, residential or commercial. Whether you need to extend the walking paths around your home, want a new patio for summertime cookouts, or need a large parking lot poured for your business, we have the tools and knowledge to do the job right. Visit our contact page or call us directly at 303-433-8822 to learn how we can turn your vision into reality.