Many people don’t realize that the method for pouring concrete changes drastically based on the temperature. While it is possible to effectively pour concrete in the Winter, the method for doing so is a bit more complicated than it is in the warmer months. Let’s take a closer look at how to effectively poor concrete in cold weather.
The trick is to not allow the concrete to freeze too soon. If concrete freezes before it has cured to a strength that can resist the expansion that occurs when water freezes, the concrete will be permanently weaker. Concrete that freezes too early can permanently lose up to 50% of its strength. That can be a huge problem if the concrete is being used as any kind of foundation or in an area where it will be required to withstand significant amounts of weight.
If you know you’re going to have to pour concrete in weather that’s below 40 degrees Fahrenheit there are a few steps you need to take care of before you begin pouring.
- Preheat the water and the aggregate you are going to be mixing to create your concrete. The goal is to make sure the concrete is at the proper temperature during the actual pour. If you have to mix on-site be sure the aggregate was stored in a warm location and us warm water.
- The actual ratio of the components in your mixture may have to be adjusted if it’s really cold outside. Usually, that means increasing the amount of cement in the concrete mixture. Avoid using fly cement or flag ash in cold weather. Trust us, it’s not worth it.
When you are actually pouring the concrete, there are a few important things to consider.
- Concrete takes significantly longer to set when exposed to cold temperatures. As a result, you will likely have to remain onsite to finish up longer than normal. Be sure to build that extra time into your construction schedule.
If windchill is a major factor, utilizing a few basic windbreaks can create a double-digit temperature difference. This can be the difference between concrete setting, or freezing.
If the temperatures are cold enough, and there is no way that you can delay pouring the concrete you may need to consider creating a heated enclosure. These can be easily erected using wood or plastic and powerful space heaters.
Your end goal is to make sure your concrete has been poured and given time to set in temperatures of at least 40 degrees Fahrenheit. It’s also important to point out that you will have to wait for all of the bleed water to evaporate. Bleeding starts later and takes longer in colder weather, so be sure to plan ahead.
Pouring concrete in the Winter is not ideal, but sometimes it’s unavoidable. Unless you are working in temperatures that are below zero, it is possible to effectively pour concrete in cold weather as long as you take the necessary steps.