Homeowners

Indoor Comfort Systems

Adding on to Your Home

Like many homeowners today, you may be adding an addition to enlarge your home. You want this added space to be as comfortable as the rest of your house, which is why it is important to consider its cooling needs.

Properly Sizing Your System

When you add additional space to your home and run the air conditioning and heating ductwork into that area, it changes the load (or demand) on your system. For this reason, you (or your contractor) should ask your air-conditioning technician to do a load calculation based on the size and characteristics of the new addition. An undersized system will struggle and even freeze over on the warmest days.

To properly size a system for a home, trained technicians use an equation that factors the home’s age, the number and quality of its windows, how well it is insulated, how many stories it has, its total square footage, and local energy rates. Homeowners should ask their technicians to perform a Manual J analysis, the industry’s term for the standardized equation for properly sizing an air conditioning system. Your technician will specify the cooling capacity of the system in either Btu/h (British thermal units of heat removed per hour) or refrigeration tons (one ton being equal to 12,000 Btu/h).