You often ask at what temperature it is possible to pour concrete in winter.
The ideal temperature for concrete pouring is between +10°C to +25°C. If we can’t wait for such weather conditions, then how cold can we pour concrete?
Up to -10°C.
However, to be able to pour concrete below 0°C, several precautions need to be taken.
If you’re not using any additives, the temperature should not drop below 0°C in the three days following the concrete pouring. It’s essential to prevent the water in the concrete from freezing because it can cause irreversible damage to the structure, leading to its complete failure.
Below 0°C, use antifreeze admixture.
The antifreeze prevents the water in the concrete from freezing and accelerates the setting time. Using Mapefast CF/L is very cost-effective. For a single-wheelbarrow mixer (for C16-20 concrete), you’ll need approximately 12-24 decagrams per 12 kilograms of cement. This means that a 6-kilogram container is sufficient for 25-50 mixes.
Technical data sheet for Mapefast CF/L:
You should not concrete on a frozen surface!
If you need to concrete onto an existing concrete surface, and the temperature has been below 0°C for a while, then you need to thaw the surface.
Concrete generates heat during the curing process.
You can utilize this heat generation if your structure is at least 10 cm thick. After concreting, you need to cover the concrete and try to do it in multiple layers so that the air trapped between the layers can participate in retaining the heat.
Keep the cement in a warm place before concreting and use warm water.
At temperatures below 5°C, increase the cement dosage by 5-10%. Concrete strength is expected to decrease below 5°C. You can counterbalance this not only by increasing the cement dosage but also by generating more heat and allowing for more antifreeze admixture.
If you are concreting indoors during such cold weather, ensure that the temperature in the room reaches 5°C for a few days.
If you want the final result to be truly durable and strong, don’t forget to add ArmoTec to the concrete; this way, you can significantly improve the reduced strength caused by the cold.
