You must pour ready mix concrete at optimal temperatures to get the best outcome. But if you need to do so during winter or colder weather, know that you’ll face a few challenges, particularly with curing. There are several tasks you should do to ensure well-constructed, long-lasting concrete.

Why It’s Challenging to Pour Concrete in Winter

The right ambient temperature plays a significant role in hardening and curing ready mix concrete. It needs 50 to 60 degrees Fahrenheit to set. The water in the mixture needs to completely evaporate to bind the chemicals through the process called hydration. Such a reaction is less likely to happen when temperatures drop below 40 degrees Fahrenheit, like in winter. Apart from prolonging the curing process, cooler temperatures form ice crystals from excess moisture, further weakening the concrete structure upon setting. It also leads to cracking and breaking, affecting its structural integrity.

What Steps Should You Take?

There are two conditions to say that the ready mix concrete is vulnerable to cold weather—average temperature is below 40 degrees Fahrenheit or when air temperature remains lower than 50 degrees Fahrenheit for more than 12 hours. During this time, below are a few precautions you can take to prevent a weak or brittle concrete after pouring in cold weather:

• Never Pour on Frozen Ground: First, thaw the surface and ensure it is above freezing levels—pouring concrete on frozen subgrade results in uneven settling once it melts. Use heaters or heated blankets to prep the ground and make it more stable before pouring the mix.

• Lessen Water in the Mixture: One way to cut down on bleeding and shorten setting time is to reduce the water-to-cement ratio. Consider adding hot water into the mix to increase temperatures, or use extra cement—100 pounds for every cubic yard—to speed up the hydration process.

• Maintain Temperature: Once poured, keep the temperature at 50 to 60 degrees Fahrenheit with external heaters, heated enclosures, or concrete-curing blankets. Ensure proper ventilation in using heaters to avoid carbonation or bubbling on the concrete’s surface.  

When pouring concrete in cold weather, remember the above tips to ensure successful curing. For quality ready mix concrete, get yours from Ideal Supplies. Located in Ludlow, KY, this hardware store offers a wide variety of supplies, including sand, gravel, and mulch, to residents throughout Kenton County and greater Cincinnati. Call (859) 491-6666 to request an estimate or visit their website.