Tips for pouring concrete during colder weather

The American Concrete Institute under ACI 306 defines cold weather as an average daily air temperature of less than 40°F and/or the air temperature is not greater than 50°F for more than 12 hours during any 24 hour period.

During these conditions, make sure you:

• Protect the concrete from freezing
• Ensure the concrete is strong enough to allow for safe removal of forms
• Proper curing conditions are present to minimize cracking and ensure stability

Before you pour!

• Outline a plan. Include materials, forms, testing, and other requirements to be used.
• Determine a cold weather protection measurement for the mix.
• Plan to keep a temperature record for the concrete temperature as well as the exterior (air) temperature.
• Never pour over frozen ground, snow, or ice. Use heaters to thaw the ground before pouring.
• Determine if special considerations and strength requirements must be met; if so, protect concrete at the specific temperatures needed.
• If heated enclosures are going to be used when placing concrete in cold weather, be sure that they are windproof and weatherproof.
• If combustion heaters are used, make sure to provide proper ventilation.
• Concrete in cold weather is recommended to have a low slump, and minimal water to cement ratio, to reduce bleeding and decrease the setting time.
• Use concrete curing blankets to prevent freezing and keep the concrete at an optimal curing temperature.