The HVAC Capacity for Basements

Capacity

• Capacity is the key part of sizing: It refers to how much space the heating or cooling unit -- or both, in the case of a heat pump -- is designed to control. If you open the front panel on your unit and examine the faceplate with model information engraved on it, it should say what capacity your unit is designed for, measured in cubic feet. If not, you can do a quick search online or call the manufacturer to find out. A contractor should be able to tell you the cubic feet of your basement for comparison, or you can measure the volume of the space yourself.

Changing Basement Space

• If your basement space remains unchanged, then capacity should not be an issue. But if you are expanding your basement and using it as another room in your house, that extra space is suddenly added to the overall load on the HVAC system. Every basement is different based on its size, but if the capacity increases the cubic feet of your home to the point where it falls beyond the range of your system, you may need to upgrade your cooling and heating functions, as well.

Remodeling Basements

• A common practice used in finishing or remodeling basements is adding new insulation. This includes batting, moisture barriers, foam board and other materials. Taken altogether, these materials can prevent heat from leaving your newly remodeled basement -- and actually increase how well your HVAC system performs. You may be able to increase your basement space but also increase your heating and cooling efficiency.

Alternatives

• If your HVAC units do not have enough extra capacity for a new or finished basement, you may not have to purchase new appliances. Using a space heater in your basement may be enough to keep the basement warm in the colder months. Supplement cooling units can also be installed in the basement for an extra boost in cooling that can make up for the size of your primary HVAC system. Keep the basement well-sealed from the rest of the house when using these alternatives.