It would be wonderful if certain projects could be postponed or completed indoors once the cold weather arrives. Unfortunately, that is not how the construction industry works. There are many professional contractors who have to be outside regardless of the weather when there is a project deadline.
Whether you are a full-time contractor or a seasonal contractor, the following tips can help you when you encounter your next concrete pour in freezing temperatures. Cold weather conditions are defined as average daily high temperatures that do not rise above 40 degrees Fahrenheit, and the air temperature does not rise above 50 degrees in a 24 hour period.
Site Preparation
It is essential that you prepare the site prior to pouring the concrete. This means that standing water, ice, and snow will need to be removed from the area you are working in.
Site preparation can include similar strategies used in the removal of water, snow, and ice on roadways. Salt, brine or another type of mixture that can quickly melt frozen liquid can be used. However, concrete should never be poured on the ground when it is frozen.
Pour Concrete During The Warmest Time Of The Day
When the temperatures are hovering around 32 degrees Fahrenheit for most of the day, it can be challenging to determine the best time of day to pour the concrete. Most contractors prefer to pour concrete during the daylight hours so they can take advantage of the heat that is created by the sun. Click here for more information.
Keep Concrete Warm
Just like you want to pour concrete during the warmest temperatures possible, you also want to ensure that the concrete mixture you are pouring remains warm as well. It will be impossible to pour concrete that is frozen, and this could delay your project by hours or even days.
Make Sure There Is A Minimal Amount Of Water In The Concrete Mixture
A concrete mixture is created when the concrete powder is combined with water. An adequate amount of water must be maintained in the mixture in order to achieve a workable concrete mixture. Also, keep in mind that the water used should be room temperature or warmer.
Embedded Items Should Be Warm
Any items that will be embedded in the concrete should also be warm. Some of the most commonly embedded items in concrete are:
- Wire
- Wire mesh
- Rebar
These items must be warmed prior to coming into contact with fresh concrete.
A Fresh Concrete Pour Must Be Protected From Freezing Temperatures
Once the concrete has been poured, the concrete will need to be protected from the freezing temperatures for at least 72 hours. The concrete can be protected through several methods including:
- Heaters
- Insulated blankets
- Loose hay
- Insulated forms
Be sure all of the corners and protruding rebar are also covered.
Prevent Water Accumulation For One Week
After the concrete slab has been completely poured, the concrete slab will need to remain dry for a period of seven days. By preventing water, ice or snow to accumulate on the fresh slab, the concrete will be able to cure effectively. It will also reduce the chances of shrinkage and surface cracks.
Freezing temperatures can be brutal, especially when you are trying to pour concrete. The good news is that these tips will help you have a successful, completed and error-free outdoor construction project.
For safety rules while concreting; visit: https://www.worksafe.qld.gov.au/claims-and-return-to-work/rehabilitation-and-return-to-work/suitable-duties/resources-to-identify-suitable-duties/concreter