I really need to pour some concrete in the next couple days. Not a big area about 6�12? This is the forecast.
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Never poured when below freezing temperatures were forecast. What precautions do I need to take?
You should not pour it on a surface which is frozen. Sometimes you have to make an enclosure and heat it to thaw the granulars and soil.
You need to order the concrete heated i.e. made with hot water so when it arrives on the job site it is protected for a while.
Concrete generates heat as it cures, but a limited amount when the slab is thin
You need to have a 6' high wind barrier in place to stop wind sweeping across the surface. I would consider insulating the forms in some fashion. Often straw is used.
You need to have insulated tarps on hand. Essentially like bubble wrap in tarp form. Put them over the surface as soon as finishing is completed.
If it is going to be very cold, the tarps should be elevated above the concrete and heat added to the enclosure.
Do NOT use an open flame heater as they produce CO2 which is harmful to the quality of the concrete.
You need to keep the concrete above freezing for at least 7 days, preferably more as the curing time is 28
The sooner you stop keeping the concrete warm, the curing process stops until the temp rises so it will not have its full strength.
You need to have a way to monitor the temp within the enclosure so if things are starting to get close to freezing temps, you can take more drastic action.
Leave the forms on as long as possible to protect the concrete edges.
Only on large projects would pouring in cold weather be done to stay on schedule. It involves risks and extra costs to wait for a break in the weather.
This link would be a good reference:
Cold Weather Concreting
Dave M7040