Indicators of Good Ductwork Design

February 25, 2016

If your heating and cooling systems were underperforming, you would want them repaired or replaced. This could essentially be the case in your Des Moines home if your ductwork design is losing airflow.In addition to increasing your energy bills, poorly-designed air ducts create comfort problems and contribute to poor indoor air quality. Whether you are designing a new home, retrofitting your ducts, or making simple repairs, use these four principles that are indicative of good ductwork design.


Work with an HVAC contractor that sizes your ductwork based on sound building science, as outlined by the Air Conditioning Contractors of America (ACCA). Proper duct sizing to each room of your home is a methodical process that uses heat gain/loss measurements, the size of your furnace and A/C, and many other factors.

Air Supply and Return

The bare minimum of return ducts and grilles should be one per floor of living space. Ideally, you want to install a return grille in each room that has a supply register. This may be more practical in many instances by installing jumper ducts and door, wall, and transfer grilles to provide free airflow to the return ducts.

Duct Location

Ducts are often installed out of sight in the unconditioned spaces in your home. If you can't install the ducts within the conditioned areas, make sure the air ducts are insulated either by design or with rigid foam board or fiberglass rolls.


Most ducts are fabricated from sheet metal. Metal joints should be fastened with sheet metal screws. Mastic paste is applied to seal up thin gaps, and metal tape should be used to wrap the connections.

Call the Lozier Experts

If you would like an evaluation of your Des Moines home's ductwork design, please contact the experts at Lozier Heating & Cooling today!Our goal is to help educate our customers in the greater Des Moines, Iowa area about energy and home comfort issues (specific to HVAC systems).