Whether a fan, air handler or ductwork, mechanical equipment is BIG. It has the single largest impact on space allocation of all MEP systems. It can limit occupiable space, require the lowering of ceilings and create objectionable noise. Considering these negative attributes, it is a very fair question for Owners and Architects to ask “What value am I getting for allowing this stuff in my building?” Fortunately, the positives are many.
The obvious of course is comfort. Gone are the days when operable windows were considered an acceptable strategy to ventilate buildings and maintain comfort. Today’s more sophisticated employees, hotel guests, restaurant patrons and apartment dwellers expect high performance HVAC systems that keep them comfortable in all seasons. This means controlling temperature and humidity as well as purging the air of noxious odors and potentially harmful chemicals off-gased from building components and furnishings.
In addition to the occupants’ expectations of comfort, modern building codes dictate that mechanical systems incorporate many features to promote health and save energy. Conforming to these codes often requires additional equipment such as energy recovery systems, economizers, dedicated outdoor air systems and MORE DUCTWORK. The advantages to these system components may not seem apparent but are actually very tangible. Energy recovery systems recoup some of the cost of cooling and heating the air in conditioned spaces. It is often possible to eliminate conventional exhaust systems by utilizing the energy recovery systems’ integral exhaust to serve restrooms and similar spaces that need to be exhausted for odor control. Eliminating the redundant system can help mitigate the increased first cost of the code-mandated energy savings feature. In addition, incorporating an energy recovery system into the mechanical design effectively reduces heating and cooling loads allowing smaller refrigeration-based mechanical systems to be utilized. Smaller equipment means less refrigerant and less energy used. These benefits further mitigate the cost of these systems. Likewise, economizers can provide essentially free cooling when outside air conditions are appropriate. Dedicated outdoor air systems effectively dehumidify the significant amounts of outdoor air required to properly ventilate schools and other high occupancy buildings. Stated plainly, they do what conventional off-the-shelf packaged and split system equipment cannot. All of these systems can play an important role in achieving points for LEED certification and Green Building programs as well.
Proper selection of equipment is critical. In regard to fans, larger fans rotating at slower speeds can move as much air as smaller fans at faster speeds. The advantage of larger, slower fans is quieter operation with the added benefit of smaller motors and associated energy savings. Another win for the BIG guy!
Strategically allocated space in mechanical rooms or above ceilings can place mechanical equipment close to the areas served minimizing ductwork thus reducing first cost and ensuring more efficient operation. Attention to the mechanical systems’ requirements during the development of the structural design can create more accessible space that can reduce installation time and cost, and avoid the dreaded schedule and budget busting RFIs that result from failure to coordinate.
At BIG RED DOG, our engineers are cognizant of the effect mechanical equipment can have on space plans and aesthetic themes. We strive to work with our clients and co-consultants to integrate the mechanical systems with building elements while ensuring optimized functionality. When properly coordinated with the architectural and structural design, mechanical systems can promote human comfort and health, while saving energy with a minimum impact on space and first cost. BIG really can be BETTER!