When pouring concrete in winter, you must carefully manage the cold weather’s impact to ensure the integrity and durability of the concrete.

Fresh concrete needs to be protected from freezing until it has reached a minimum strength of 500 pounds per square inch (psi), which typically occurs within the first 24 hours after placement. To properly cure and avoid damage from freezing temperatures, concrete should be maintained at a temperature of at least 50°F for a minimum of the first 48 hours. This is crucial for the hydration process, which is necessary for the concrete to achieve its intended strength.

Here are essential precautions for successful winter concrete projects:

  • Concrete should not be poured on frozen ground. Use heated enclosures or ground heaters to keep the site above freezing prior to pouring.
  • Maintain concrete at a temperature above 50°F to protect the concrete from freezing temperatures and to retain the heat generated by the hydration process for at least the first 48 to 72 hours.
  • Keep the concrete covered with insulating blankets for at least seven days, checking periodically to ensure it remains at an appropriate temperature.
  • Consider adding chemical accelerators to the concrete mix to reduce the setting time which is crucial during colder weather.
  • Avoid Adding Extra Water. Extra water can increase the risk of freezing and weaken the concrete. Stick to the recommended water-to-cement ratio to ensure the strength and durability of the concrete.
  • Schedule pours during the warmest part of the day and monitor weather conditions closely. Avoid pouring concrete immediately before or during a severe cold spell.

By following these precautions, you can successfully pour concrete in winter, ensuring the structural integrity and longevity of their construction projects.