Even with the onset of winter, construction must continue. Problems from working in cold weather can include slowing the hydration of cement in mortar mix, lengthening cement curing time.
Mortar mixed during cold weather often has lower water content, increased air content, and reduced early strength compared with those mixed during normal temperatures. Mortar is often mixed with heated materials to produce performance characteristics associated with mortar mixed at normal temperatures, or with admixtures which may improve the early strength and plasticity of the mix. Water, sand, or both are often heated for use in mortar in cold weather. However, heating prepackaged materials such as cement and hydrated lime has long been a problem for brick masons.
Frozen Mortar Will Not Work
Mortar freezing should not be allowed to freeze. Mortar that freezes is not as weather-resistant or as watertight as mortar that has not frozen. Significant reductions in compressive and bond strength may occur. Mortar with water content over 6-8% of total volume will experience disruptive expansive forces if frozen due to the increase in volume of water when it is converted to ice, and the bond between the brick or block and the mortar can be damaged or destroyed.
The Benefits of Concrete Curing Blankets
Experts recommend covering newly-laid brick or block with insulating blankets when temperatures are below 40°F, and using heated enclosures when the temperature is below approximately 25°F. Powerblanket® concrete curing blankets eliminate the need for heated enclosures and are the best option when it comes to insulating blankets. They maintain the proper curing temperature no matter what changes in weather occur, keeping the mortar bond strong and lasting. Instead of building enclosures, concrete curing blankets can be easily hung on newly-laid walls, eliminating the need for constructing enclosures or other temporary structures.
Concrete curing blankets can:
- Keep the sand pile and dry mix bags warm and dry
- Ensure that crews can lay brick or block in any temperature
- Achieve durable and long-lasting walls, with predictable scheduling and minimal crew downtime caused by poor conditions
- Maintain proper curing temperature regardless of external conditions
- Hang easily
Hot Boxes are Problem Solvers
Whether you need a means for protecting temperature-sensitive materials in storage, or you need a heating solution for onsite temperature maintenance, consider the Powerblanket Hot Box. This versatile heating solution accommodates remote-location use, job site heating, the transporting of temperature sensitive materials. Imagine transporting materials from job to job, knowing that your mortar, sand, and/or dry mixes will be ready for use when you arrive and well into the day. The revolutionary design of Powerblanket Hot Boxes provides uniform heat to all materials stored inside. This reduces the chance of having any hot and cold spots. If stored properly, masonry materials, chemicals, industrial products, and temperature sensitive materials will last longer and be more effective.
Hot boxes are:
- Versatile and easy to use for many different applications
- Easily transported
- Provide even heating
- Time, material, and money saving