HVAC Load Analysis: Importance In Commercial Building Design

The design and development of a commercial building is no small feat. The time and effort it takes to make a successful design from paper and turn it into a robust structure are tremendous. Many critical functions need to be conducted for the creation of a great commercial building, one of which is the installation of an HVAC system. When you’re installing an HVAC system, you need a dependable system. You need a system that has equipment powerful enough to sustain heating or cooling of the space without breaking the bank due to high energy expenses. Ergo you need to conduct HVAC load analysis for commercial buildings so that they might have a highly effective & energy-efficient system.

How Is HVAC Load Analysis for Commercial Buildings Done? 

HVAC Load analysis is a very complex calculation that is done with extreme precision. This calculation is conducted by doing a survey of all the rooms in a building and identifying potential heat, cold, etc. sources present. Then, based on those factors the potential load on an HVAC is calculated. Once we know the load that will be put on an HVAC system, we recommend hardware equipment for your HVAC system that suits your and ASHRAE commercial design standards. 
HVAC Load calculation is a highly specialized, time-heavy, and complex undertaking that only highly qualified, skilled, and experienced professionals can do. With the help of such professionals, you can successfully conduct your HVAC thermal load analysis to reach optimal building performance. The first step that needs to be taken for optimal climate control within the building is understanding the type of building we are working with. The type of building will determine the type & intensity of the task at hand as different buildings will have different needs.

A thing that property owners need to understand is that to analyze the HVAC requirements of a building, professionals need a lot of peripheral information. For example, information such as the building’s architectural plans, previous HVAC system designs (if any). The load calculation procedure commences once all prerequisite data is made available. Generally, load calculation is done in two ways per ASHRAE commercial design standards. 

Here are the two methods of conducting HVAC load analysis: 

• Manual – In this process the data is gathered from a survey conducted on the building and complementary sources/documentation is tabulated & analyzed as per codified equations & pre-defined parameters. The equations and table values used are determined based on the building structure, geometry, construction material, etc. 

• Automated – In this process as the name suggests the process is largely automated and software takes the lead. HVAC designers use software systems like Trace 700 and HAP (Hourly Analysis Program) to perform complex HVAC thermal load analysis & calculations. This procedure still requires manual data, but many of the redundant tasks are automated for increasing the accuracy & speed of the procedure.

Our organization recently conducted the HVAC load analysis for 19 Grainger branches spread out all over the United States. During our analysis, we visited all the sites, and recorded, monitored, and analyzed the data that we gathered to form our HVAC strategy. We used a multitude of parameters to gather and process the data generated. 

Our load calculation procedure includes, but is certainly not limited by the following data points; 

• Building appliances wattage usage
• Construction type, insulation factors, and area of the walls
• Construction type, insulation factors, and area of the windows
• Roof area, insulation factors, and construction type
• Floor construction type, area, and insulation factors
• Space areas of the building
• Electricals & lighting of the building
• Total maximum & minimum occupancy of the building at any given moment

Quintessential Reasons Why You Need To Conduct HVAC Load Analysis

The prime reason for installing an HVAC system is to create a comfortable indoor environment. Ergo, the size of your commercial HVAC system represents the amount of energy it needs to do the same. If you install a system that is too big for your needs, then it would cycle on & off at frequent time intervals resulting in uneven temperatures. Similarly, a system that is too small will end up operating overtime, but always end up failing to keep the occupants comfortable. Hence you must conduct a thorough HVAC load analysis to make sure you have the equipment that is just the right size & capacity. 

You must understand that everything has a profound impact on your HVAC system capacity and energy consumption. Load analysis and calculations help in determining how these factors that impact your HVAC system can be tackled and mitigated for uninterrupted climate control. A poorly designed HVAC system that doesn’t factor in the levels of building insulation, window size, occupancy size, etc. will have suboptimal functionality and lose energy, thus driving up your energy consumption and cost to maintain such a system.  
A commercial building with an HVAC system that was built with thorough load calculation & analysis will help keep your monthly energy expenses under check. This is due to you using the right-sized equipment that lasts longer and requires fewer maintenance checks, thus saving you money in the long term. Equipment that is undersized, oversized, or doesn’t meet the ASHRAE commercial design standards will be a nightmare for you!