Construction is a year ’round activity, and if you do construction in Pennsylvania, you’ll have to face the fact that sooner or later, you’ll need to pour concrete in very cold temperatures. So how cold is too cold to pour concrete?
What Temperature Is Too Cold to Pour Concrete?
There’s no specific temperature minimum for pouring concrete. However, you need to be aware of the effect of cold weather on concrete and the fact that you’ll have to take special precautions while pouring concrete in very cold weather.
Effects of Cold Weather on Concrete and How to Combat Them
If you place your concrete in cold weather, there’s a danger that when it sets, it won’t have the strength and durability required for your application. What you’re trying to avoid is having the concrete freeze after you pour it but before it sets.
The American Concrete Institute defines cold weather for concrete pouring as below 40 degrees Fahrenheit (5 degrees Celsius). If the average air temperature on the day you’re pouring is 40 degrees or less, you’re in a cold weather concrete pouring situation. In addition, if you expect that air temperature will not rise above 50 degrees Fahrenheit (10 degrees Celsius), for more than half of any 24-hour period, you should consider it a cold weather situation.
Cold Weather Concrete Curing
To prevent the concrete from freezing and allow proper curing to take place in cold weather, you need to heat your concrete to the appropriate temperature. You want to be careful not to overheat your concrete to avoid excessive drying.
If the air temperature is between 30 and 40 degrees Fahrenheit, you’ll want to make sure your mixed concrete maintains a temperature of between 55 and 60 degrees. Between 0 and 30 degrees, maintain your concrete at 60 to 65 degrees. If you’re pouring concrete in sub-zero temperatures, make sure your concrete maintains a temperature of 65 to 70 degrees.
For normal-set concrete, you’ll need to maintain this temperature for two days if there’s no load on the concrete and it’s not exposed. If it is exposed, maintain the temperature for three days. With accelerated-set concrete, you can maintain for only one day unexposed and two days exposed.
While your concrete should be safe once you reach 500 PSI because sufficient hydration will have taken place, it should have a compressive strength of at least 4,000 PSI before you subject it to repeated cycles of freezing and thawing.
Turn to Union Quarries for Quality Concrete in All Kinds of Weather
If you have concrete needs in central PA at any time of the year, remember that the company to turn to is Union Quarries. We’ve been providing high-quality concrete in central PA since the 1960s, and we can answer all your questions about concrete as well as provide you with ready-mix concrete, stone, aggregates and whatever else you need for the job. To learn more, get in touch with us now!