Rebar Alternatives Save Big $$$

Contact Us

Fill out the form below to request more information from our Bladensburg location.



    View our privacy policy

    MD: Bladensburg (HQ)

    (301) 927-8300

    4700 Annapolis Road, Bladensburg, MD 20710, USA

    Mon-Fri 6:30AM to 4:00PM Saturday 6:30AM to 12:00PM Sunday CLOSED

    Get In Touch with someone at MD: Bladensburg (HQ)
    (301) 927-8300






      Response time within 4 hours

      Cold Weather Concreting

      David Welch | September 8, 2021

      While it gets cold in the winter, that doesn’t mean you have to stop concrete form work. Taking the right precautions can mean you can work year-round.

      Why Cold is a Challenge

      As with anything that contains water, ice can form at cold temperatures. Finished concrete can certainly withstand these cold temperatures. However, fresh concrete has lots of free moisture can lead to problems in cold weather if not properly addressed.

      Fresh concrete contains three components: cement, aggregate, and water. It’s the last component that is most challenged by cold weather [when the average daily temperature falls below 40°F [4°C] for more than three successive days].

      At or below 40°F water begins to crystallize into ice. It is the formation of these ice crystals that disrupts the normal curing processes, which can reduce final concrete strength by >50%. These conditions remain extremely problematic until the minimum compressive strength of 500 psi is attained. Most concrete takes about 2 days curing at 50°F to reach this strength.

      Cold weather also slows down the cement hydration reaction. Special attention should be paid to the slower rate of setting and strength gain, particularly in scheduling finishing operations and form removal. A good rule of thumb is that a drop in concrete temperature by 20°F [10°C] will approximately double the setting time.

      Furthermore concrete should not be exposed to freeze/thaw cycles until it has attained a minimum compressive strength of 3500 psi. Concrete that encounters these conditions either during construction or use should always be air-entrained to better account for these more severe conditions.

      Ways to Address

      There are several ways to address these common challenges, to make sure your concrete measures up even in the cold.

      • Heat- directly offset the cold air temperatures by using job site heating units, hot water in the mix
      • Cover- insulating blankets help to retain heat and moisture. They also limit evaporation due to wind and other environmental conditions. (learn more about evaporation)
      • Enclose- work similar to direct covering. Be certain to not also enclose a combustion heater without proper venting, as this will produce carbon monoxide as well as lead to surface carbonation.
      • Admixtures- use of accelerating admixtures (Type C and E) can help offset the delayed setting time that occurs due to colder to temperature. Some accelerators contain chloride, which can accelerate corrosion of any embedded rebar and impact coloring.
      • Mix modification
        • Early Strength- Type III (high-early strength) cement
        • Use Less Moisture- reduce slump, entrain air, or use water reducing admixtures (Type E)
        • Make Concrete Cure Quicker: reduced SCM (supplementary cementitious material) content
        • Make Concrete Cure Hotter: more cement
      • Thicker pours retain heat better, and generate more heat during the curing process

       

      Need concrete blankets? Does your supplier shrink from the challenge of cold? Let Bay Ready Mix and Parker Block put you on good footing.

      Ready Mix Sales ManagerDavid Welch

      Location
      MD: Annapolis Junction
      Languages
      English

      Latest News

      Ernest Maier and Gomoljak Counter Price Sheet

      Ernest Maier and Gomoljak Counter Price Sheet

      Pricing accurate as of 4/18/2022 and valid for Annapolis, Bladensburg, and Gaithersburg locations (contact us for bulk pricing and delivery): […]

      Read More
      Masonry Veneer Installation System- Cost Savings Calculator

      Masonry Veneer Installation System- Cost Savings Calculator

      Use this calculator to determine your potential savings when using Laticrete’s Masonry Veneer Installation System (MVIS) over traditional lath and […]

      Read More
      Climate Change is Changing Construction

      Climate Change is Changing Construction

      Climate change is supercharging natural disasters. While not new, the frequency and severity of the natural disasters that occur is […]

      Read More
      Fiberglass Rebar- Saving You $$$

      Fiberglass Rebar- Saving You $$$

      Steel prices going up? Ernest Maier is now stocking fiberglass rebar to save you money. <50% cheaper for 20 feet […]

      Read More
      Winner of the 2022 Top Workplaces Award for Leadership

      Winner of the 2022 Top Workplaces Award for Leadership

      “ Bladensburg MD, April 28, 2022 – Ernest Maier, a Mid-Atlantic based construction material manufacturer and distributor, has been recognized […]

      Read More