Pouring Concrete in Cold Winter Weather
It would be nice if projects stopped (or at least went indoors) during the cold winter months, but that’s not how this profession works. We have to be outside in the good and the bad to complete a project.
Whether you work with concrete on a daily basis, or every few weeks or months, our sponsor QUIKRETE gave us some helpful tips for your next cold winter weather concrete pour. Cold weather conditions occur when the average daily temperature is less than 40 degrees Fahrenheit; and the air temperature is not above 50 degrees Fahrenheit for more than 12 hours during any 24-hour period.
10 Best Practices for Pouring Concrete in Cold Winter Weather
- Beginning with site preparation, any snow, ice or standing water needs to be removed from the work area prior to pouring. And do not pour concrete over frozen ground.
- Place concrete early in the day to take advantage of the heat produced by the sun during daylight hours.
- Use an air-entrained, fiber reinforced and crack resistant concrete for your cold winter weather concrete pour. The special formulation of the concrete has superior freeze/thaw durability to help reduce cracking from drying shrinkage and spalling concrete. Alternative options are concrete designed for higher early strength because of its high volume of cement or concrete that sets quickly.
- Keep the concrete in a warm area prior to mixing.
- Incorporate the minimum amount of water necessary to achieve a workable mix. Use warm (less than 140 degrees Fahrenheit) water for mixing with the concrete.
- The temperature of any items to be embedded in the concrete (rebar, wire mesh, etc.) needs to be above freezing before coming into contact with the fresh concrete.
- Once poured, protect the concrete from freezing for a minimum of three days through the use of insulated blankets, heaters, insulated forms, enclosures or loose straw layered between waterproof covers. Pay close attention to cover all edges and any protruding rebar.
- After this protection is removed, apply a waterproofing concrete sealer to the concrete as a curing compound. The sealer will eliminate the need for water curing.
- Following initial placement, prevent any snow, ice or standing water from accumulating on the new slab for at least seven days.
- A little tender loving care goes a long way. As the concrete cures, a hydration reaction generates internal heat. The longer the temperature is maintained, the stronger the concrete becomes, so cover the job for several days with insulating straw and thermal blankets. Powerblanket is a good way to maintain internal heat. And once the concrete’s hard, do not use de-icing salts, which will corrode the surface and allow water to permeate, freeze and eventually crack your fine work.
Other articles from QUIKRETE:
- Decorative Concrete Stains for Your Next Project
- How to Resurface Concrete
- How to Set Posts in Concrete
- How to Finish Concrete
- How to Repair Concrete Damaged by Winter Weather
Now we want to hear from you. What best practices would you add to this list based on your experience pouring concrete in cold winter weather.