When the mercury starts dropping in the fall, general contractors and construction managers must maintain proper temperature, relative humidity and ventilation on their jobsites. Temporary heating and ventilating equipment and services are an important and necessary part of the solution to keep jobsites running smoothly throughout the winter months.

During the construction process, thousands of gallons of water are used in the construction of most commercial buildings. Concrete mixtures, masonry, drywall compound, fireproofing, paint, floor coating and varnishes all begin using a water base. When the finishes dry, the moisture is given up into the interior spaces of the building. Knowing this, it is as important to keep the building ventilated and dry as it is to maintain comfortable temperatures.

There are advantages to choosing the correct temporary heating equipment for an application. For example, direct-fired make-up air heaters may be the best choice for providing a system of both heat and ventilation in an enclosed building. However, smaller propeller fan, tube-style heaters are best suited for work in temporary poly or canvas enclosures. The following is an overview of different types of heating equipment and their applications.

Direct-fired make-up air heaters

Fossil fuel burning equipment is categorized as either “direct fired” or “indirect fired.” Direct-fired heaters do not have a heat exchanger for the exhaust gases, and all products of combustion go into the space being heated. Direct-fired heaters can be very fuel-efficient since no energy goes up a chimney. Nationally recognized testing laboratories approve this type of equipment for multiple applications since it is very clean burning.

Make-up air heaters should be installed to draw 100-percent outside air for proper heat distribution and ventilation of the construction processes. High-cubic feet per minute (CFM), low-temperature discharge units typically feature a centrifugal-style blower wheel and an electronic modulating gas control system for maximum fuel efficiency and inside temperature and humidity control. The lower discharge temperatures of these units will mix better with internal air and reduce heat stratification. To provide reasonable heat retention, these units are best used when the walls and roof are in place, and windows and doors are either installed or covered with a double poly system.