Experts agree—the best temperature to pour concrete is between 40° – 60°F. When temperatures dip below 40°F, the chemical reactions that strengthen concrete slow down and can lead to weaker concrete.

Temperature can have a detrimental effect to concrete strength development. However, proper cold weather concrete curing will enhance concrete strength development. Hot weather is defined as any combination is high ambient temperature, high concrete temperature, low relative humidity, and wind velocity.

Typical specifications require the temperature of the concrete during placement to be within a range of 10°C to 32°C (50°F to 90°F).

Concrete sets more slowly when it is cold—very slow below 50 degrees Fahrenheit and below 40 degrees Fahrenheit, the hydration reaction basically stops and the concrete doesn’t gain strength. Anything below 40 degrees Fahrenheit will slow the curing process and may even stop it altogether.

Cold Weather Concrete Tips. You can pour in cold weather, as long as certain precautions are taken. Concrete set time at 70 degrees is approximately 5 hours, at 50 degrees it is 10 hours, at 30 degrees it’s up to 20 hours (if the concrete doesn’t freeze!).

Use a good quality curing compound if you are unable to maintain concrete temperatures above 50° degrees Fahrenheit for three to seven days. Maintain the concrete temperature above 40° degrees Fahrenheit for at least four more days after the use of the insulation blankets or heated enclosures.

Plastic Sheeting Can Permanently Discolor Concrete. Adverse weather conditions such as rain, snow, or freezing temperatures often make it necessary to protect concrete by covering it. If the concrete is completely covered with plastic, no outside moisture can penetrate to contact the slab.

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It’s advised that concrete be cured at a moderate temperature between 50 °F – 90 °F. In a perfect world, the temperature of fresh concrete should be above 50 °F, but cured and maintained at 50 °F.

150-200°F

In cold-weather concreting, when the ambient temperature is too low, the hydration of the cement will drastically slow down, or even completely stop, until the temperature increases again. The general guidelines suggest that the concrete curing temperature must be maintained at >5°C (40°F) for 48 hours (ACI 306).

Experts agree that the best temperature to pour concrete is between 50-60 °F. The necessary chemical reactions that set and strengthen concrete slow significantly below 50 °F and are almost non-existent below 40 °F.

Concrete in cold weather absolutely does need to be cured—the surface can dry out even faster than in warm weather, if the concrete is warmer than the air.

High summer temperatures, low humidity, direct sunlight, high concrete temperatures and even modest wind velocity can cause concrete surface cracking (plastic shrinkage cracks). Plastic shrinking cracks occur when surface moisture evaporates too rapidly. …

well the answer of your question is simply yes, the heat of hydration may cause cracking in cement or concrete especially if in mass concrete constructions: the rise of temperature in mass concrete due to progression in heat of hydration — cause serious cracks.

It is possible to add chilled water, ice or liquid nitrogen to keep concrete temperatures under control. Producers can also wet and shade stocked aggregates to keep concrete temperatures under control.

To maintaining cool concrete in hot weather, the temperature within the concrete can be reduced by using cool water or ice as part of the mixing water. Additionally, spraying aggregates with water can help keep the concrete cool.

Retarding admixtures are used to slow the rate of setting of concrete. By slowing the initial setting time, the concrete mixture can stay in its fresh mix state longer before it gets to its hardened form. Use of retarders is beneficial for: Complex concrete placement or grouting.

In most areas, all concrete placement is recommended to take place before 10 a.m. On many larger projects, concrete is placed at night or during the early morning hours to avoid the extreme heat of the day and to allow concrete to set before afternoon rains.

Many techniques are available to reduce concrete temperature , such as cooling the mix ingre d i e n t s or using chilled water, crushed ice, or liquid nitrogen to cool the entire mix. In summer, the cement tem- p e r a t u re can be high, so it may be necessary to store cement longer to let it cool.

Why Does Concrete Get Hot? Concrete gets hot due to its contents: water, cement, and aggregate (sand, stones, and/or gravel). When sunlight shines on the surface, this combination of ingredients goes through a chemical reaction that generates a thermal mass, absorbing the heat given off by the sun.

The easiest way to cool off your backyard is to create some shade from the sun. If you’ve got a pergola, like blogger Molly Madfis of Almost Makes Perfect, add a shade fabric on top or beneath for extra sun protection. Bonus: It can keep leaves and sap off your outdoor furniture.

How to Beat the Summer Heat by Keeping the Roof Cool

1. Grow a roof garden. One of the best ways to keep the roof cool is by growing your own rooftop garden with green grass and potted plants.
2. Paint the terrace white. Heat gain can be considerably reduced by turning the roof into a reflective roof surface.
3. Add shade.
4. Go for heat-resistant flooring.
5. Install solar panels.

Since dark surfaces are better heat absorbers, traditional cool roofs are white. Berkeley Lab research has demonstrated that raising the solar reflectance of a roof from about 20 percent (dark gray) to about 55 percent (weathered white) can reduce cooling energy use by 20 percent.

Best Roofing Materials for Hot Climates

• Terracotta: Terracotta and clay have been in use for decades.
• Slate Tiles: Slate tile is a natural material that is usually preferred by homeowners with an antique taste.
• Green Roofs: Green roofs not only look extremely attractive, but are also eco-friendly.
• Solar Cells:
• EPDM:
• Metal Sheets:
• Concrete Tiles:
• White Tiles:

Bituminous sheets with silver coating on one side are available for top insulation of the roof. They not only reflect heat and insulate but also protect the roof from water leakage. They are about 8 mm thick and have a silver coating on the exposed side. They are glued to the roof with bitumen liquid.

Yes, water on the roof will help cool it. Cooling with liquid water running off from a sprinkler is not efficient, but evaporative cooling from a small amount of water (like a periodic sprinkle) is very efficient. 1 gallon of water consumes 8000 BTU as it evaporates.

Here are the DIY steps for the same:

1. Purchase aluminium foil, thermocol sheets (of thickness one inch each), and gunny bags.
2. On the roof, just above the room that you want to keep cool, spread the gunny bags evenly.
3. Then place thermocol sheets above the bags and cover the whole thing with aluminium foil sheets.