How Long Does It Take Concrete to Dry?

Typically, when people ask how long it takes concrete to dry, they want to know how long it will take until they can walk or drive on it. Concrete generally takes 24 to 48 hours to dry enough for it to be suitable for foot traffic and requires about 5 full days to dry before a vehicle can drive over it, depending on ambient temperatures and the mix used.

There are some technicalities when distinguishing between concrete “curing” and concrete “drying”. For starters, concrete technically doesn’t dry – it cures. Nevertheless, these terms are often used synonymously and interchangeably when they refer to two different processes, explained below.

What Does It Mean to Cure?

By definition, concrete curing is the process of maintaining adequate moisture within concrete within a proper temperature range to allow the concrete to achieve the desired properties for use. In other words, concrete hardening is essentially what provides enough strength and durability to the material, enough to be used for an intended purpose – the process of concrete hardening enough to walk or drive on it, for example. Once concrete is hardened, it still needs to evaporate moisture after it has solidified completely. This process begins after the finishing process, which is once the concrete is poured and set.

How Long Does It Take Concrete to Dry?

Concrete typically takes 24-48 hours to dry before it can be walked on and 5 days to dry before a vehicle or machinery can drive on it. It is believed that concrete will typically reach its full effective strength after about 28 days of hardening.

What Is Concrete Drying Process?

Concrete never technically dries because water isn’t intended to leave the concrete mixture. From a chemical standpoint, the water added to the concrete mixture reacts or hydrates with the cement and aggregates to form the bond. Even after concrete becomes hard enough to walk to drive over, it still contains moisture that will continually evaporate as it hydrates. The drying process involves excess moisture evaporating through the surface, which is then replaced by water within the concrete moving to the capillaries and up to the surface. This process will continue, as long as the surrounding air can hold more water vapor.

How Long Does It Take for Concrete to Dry?

Although concrete never technically dries fully, there are several conditions that influence how fast concrete can harden and evaporate moisture. A general rule of thumb is that concrete takes about 28 days to dry for every inch of thickness. Conditions conducive for concrete to dry are consistent reasonable heat above 50 degrees Fahrenheit and up to 14 days in the air and low relative humidity.

What Conditions Can Expedite the Hardening Process?

• Using slightly warmer water in the concrete mix encourages a quicker reaction and hardening time.
• Warm, sunny, dry weather conditions always lead to faster drying times over low temperatures or extended periods of rain.
• Adding calcium chloride as a compound in the concrete mixture before pouring can quicken the set time.