How Long Before You Can Walk or Drive on New Concrete?

How soon you can walk on new concrete depends on the mix. On the QUIKRETE data sheets checked for this guide, the walk-on times are 3 hours for one mix, at least 4 hours for another, and 10 to 12 hours for a third. For driving, the driveway guidelines posted on the Illinois Ready Mixed Concrete Association’s website say not to drive on new concrete for at least 7 days.

The data sheet for QUIKRETE Concrete Mix (No. 1101) gives no walk-on or drive-on time, so this guide does not give one for it either.

Setting, curing, and drying are three different things

Setting has a time of its own. The National Ready Mixed Concrete Association (NRMCA) writes about the setting time of concrete, and says concrete at a low temperature has a slower setting.

Curing is a job you do. NRMCA describes it as maintaining newly placed concrete at adequate moisture and temperature conditions so that it can develop the properties, such as strength and durability, the mixture was designed to achieve.

Drying is what curing holds off. NRMCA says the objective of curing is to prevent loss of moisture and maintain a favorable temperature, and that without an adequate supply of moisture the cementitious materials in concrete cannot react to form a quality product. Drying comes at the end: the same document says the termination of curing should allow for gradual drying of the concrete.

Walk-on time depends on the product

Of the four QUIKRETE data sheets checked for this guide, three give a walk-on time and one does not:

QUIKRETE mix	Walk-on time on the data sheet
Q•MAX PRO Concrete Mix	3 hours
Fast-Setting Concrete Mix	Wait at least 4 hours before walking on the slab or placing heavy objects on it
QUIKRETE 5000 High Early Strength Concrete Mix	10 to 12 hours
Concrete Mix (No. 1101)	Not stated

The spread is wide: the longest figure in the table is more than three times the shortest. That is why a single rule for all concrete does not hold, and why this guide gives none for a mix whose data sheet is silent.

If your bag is not one of these, look for a walk-on time on the bag or on the maker’s data sheet for that product. If you had ready-mix delivered, ask the supplier.

Vehicles: at least 7 days

The driveway guidelines posted on the Illinois Ready Mixed Concrete Association’s website put it in one line under homeowner care: do not drive on the new concrete for at least 7 days.

Two things about that number. It is a minimum, not a promise that every slab is ready on day 7. And it comes from guidelines for driveways, which elsewhere call for a mix with a compressive strength of at least 4,000 psi at 28 days and refer the reader to local code requirements.

None of the four QUIKRETE data sheets above gives a time for vehicles. If you poured a driveway or a parking pad from bags, ask the maker before you park on it.

How to cure it

NRMCA says curing begins immediately after placement and finishing and should continue for a sufficient period, typically 3 to 7 days.

QUIKRETE’s data sheet for Concrete Mix (No. 1101) is more specific. It says curing should start as soon as possible and continue for 5 days in warm weather, at 70 °F or higher, or 7 days in colder weather, at 50 °F to 70 °F. Both of QUIKRETE’s periods are within NRMCA’s typical 3 to 7 days.

What is at stake is strength. NRMCA says concrete in a dry environment can lose as much as 50 percent of its potential strength compared with concrete that is moist cured.

QUIKRETE’s Concrete Mix data sheet has a section on specific curing methods. For another mix, follow the curing instructions on its own sheet.

What temperature does

Cold slows setting and strength gain. NRMCA’s rule of thumb is that a drop in concrete temperature of 20 °F will approximately double the setting time.

For curing, NRMCA says the temperature of placed concrete should be maintained above 50 °F. QUIKRETE’s Concrete Mix data sheet says to protect concrete from freezing during the first 48 hours.

Heat is not a shortcut. NRMCA says concrete cured at high temperatures at an early age will not be as strong at later ages as the same concrete cured at temperatures in the range of 70 °F.

How strength builds

Strength is still building weeks after the pour. QUIKRETE’s Concrete Mix data sheet lists a typical compressive strength of 2,500 psi at 7 days and 4,000 psi at 28 days. By that table, the mix has a little under two-thirds of its 28-day strength after the first week: 2,500 ÷ 4,000 is 62.5%.

Those are typical figures for one product. Other mixes have their own tables, and the numbers on the sheet for your mix are the ones to plan around.