Fall has arrived, and that means that here in the Pacific Northwest, as we know, cold winter weather is not far behind.
You probably wouldn’t be surprised to hear that cold weather changes how we pour concrete here at Custom Concrete Contracting. As it should. But with adequate preparation and attention to detail — both hallmarks of our process here at CCC — cold weather needn’t throw off the timelines of your projects. To help explain, we thought it’d be a good idea to talk a bit about how cold weather affects concrete installation here in Whatcom and Skagit counties.
How cold is cold?
According to the National Ready Mixed Concrete Association, cold weather is when the average daily temperature falls below 40 F for more than three consecutive days. That can happen rather quickly here in the Northwest, so we like to be prepared. In fact, with average November highs of 50 F and December and January highs of 45 F, a four-day stretch of sub-40 temps is actually pretty common.
Concrete setting in cool weather
After concrete has been mixed but before it has hardened, or set up, it is said to be in the “plastic” state. Concrete can actually freeze in this state, given all the water involved, and that’s not a good thing for the life of the concrete. To ensure good durability for a concrete installation, concrete should be protected from freezing for about two days after it’s poured — or longer, depending on how cold it is.
There are concrete temperature guidelines we follow when placing concrete in cold weather. There are both minimum and maximum temperatures for the concrete itself, depending on how cold the weather is. We can control the initial temperature of the concrete by using warmer or cooler water in the mixing process. This can actually provide long-term benefits to the concrete, as a lower initial temperature of the concrete can lead to greater strength in the end, according to the NRMCA. Concrete set at 40 F and 55 F will be weaker initially than concrete set at 73 F, for example, but by day 90, both will be stronger.
It’s important to remember, though, that there are minimum temperatures for the concrete at the initial pour, depending on the size of the concrete section. Additionally, when it’s cold outside, newly placed concrete needs to be insulated so that it retains its initial heat plus the heat generated during the setting process.
Custom Concrete has experience in cold-weather concrete
Maximizing the balance of concrete temperature, set time and ultimate strength is a delicate process, but it’s one in which we have a lot of experience here at Custom Concrete Contracting.
For help with your concrete project in the cool upcoming months, reach out to us here at CCC in Bellingham. We’d love to discuss your project.