Limits for Exterior Restoration Part 2: Temperature Control
By: James Monahan
As discussed in part 1 of this series, façade and roof restoration projects face many challenges from start to finish. However, weather can be the most unpredictable obstacle to the commencement, progress, and completion of an exterior construction project, especially in the Northeast’s climate.
Whether it’s hot or cold, the temperature is a limiting and controlling factor in the construction industry. Laborers must be wary of working under extreme heat due to the possibility of dehydration or heat stroke. It’s up to the engineers, architects, superintendents and other members of the project management team to ensure that workers are operating under safe conditions. Providing ample breaks for rehydration and rest, or even shutting down work due to excessive heat, are ways to protect the construction workforce.
Cold temperatures can limit laborers’ capabilities as well. Working 8 hour days in the frigid temperatures common to the climate of the northeast is not a safe or productive option. Again, it is the responsibility of the project management team to ensure workers are provided breaks to get out of the cold and warm up.
Besides affecting the project crew and their ability to properly perform their work, temperature extremes affect the installation of construction materials. Masonry work should not be performed when temperatures drop below 32°F within 48 hours of installation. In the event temperatures are between 32°F and 40°F, contractors must install thermal blankets over the masonry for a period of 48 hours to ensure the mortar properly cures. Inversely, masonry should not be installed when temperatures exceed 90°F because mortar can crack if it dries too rapidly. Many wall membrane waterproofing products should also be installed when temperatures are above 40°F. There is, however, low-temperature waterproofing products that can be installed in temperatures between 25°F and 60°F. Similarly high-temperature waterproofing products are also available for installation in extremely high temperatures; however, having workers perform this can raise safety issues. Additionally, primers and topcoat paints are subject to similar temperature limitations.
Weather conditions are bound to affect the progress of any construction or restoration project. And while we as engineers cannot control this reality, we can make sure that safe, responsible and humane working conditions are maintained, that common construction materials are properly handled as per project specifications, and that conditions and materials are continuously monitored throughout the various seasons of the projects we oversee.