Designing A New Duct System? Follow These Key Principles

designing a new duct tsystem detroit michiganWhen you are designing a new duct system, it’s important to be familiar with key principles of efficient duct design, and communicate your expectations clearly with your HVAC professional. Anything less than optimal duct design can mean years of excessive energy waste, poor home comfort, and an overworked heating and cooling system.

Balanced airflow — Balanced airflow is the objective of designing a new duct system. It’s achieved when the other key principles, sizing, installation and sealing, are followed to the letters “J” and “D” — that is, the guidelines on the industry standards found in Manuals J and D.

Duct sizing — Make sure your HVAC pro uses Manual J to measure heat gain/loss throughout your home. The results of the Manual J measurements are required to calculate Manual D — duct sizing. Accurate duct sizing is important for equal air movement through the supply and return ducts, and optimal performance from your heating and cooling systems.

Duct installation elements — Ducts should be located in heated/cooled spaces rather than unconditioned areas (attic, basement and crawl space). Utilize raised floors, room corners, drop ceilings and chases. Take the straightest path, avoiding sharp turns (T-branches). Install registers and grilles on inner walls closer to the heating and cooling systems, which themselves should be centrally located to ensure shorter duct runs. Multiple return grilles are preferred: one in each room containing a supply register. Utilize transfer grilles and cross-over ducts if multiple grilles aren’t possible.

Duct sealing — Metal duct seams should be secured with sheet-metal screws. This helps safeguard against ducts falling away — a much too common problem for many duct systems. Mastic sealant is applied to all metal duct seams. Use compression straps and metal tape to seal flex ducts. If you must locate duct runs in unconditioned space, insulate those ducts.

Following these key principles when designing a new duct system enhances comfort, and balances airflow to prevent outdoor-air infiltration, and helps control (minimize) pressure drops. Lastly, remember to clean or change your air filter as recommended by the manufacturer.

For more information about designing a new duct system, and any other HVAC issues, contact Aladdin Heating & Cooling. We’ve proudly served homeowners in all of southeast Michigan since 1945.

Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems).  For more information about duct systems and other HVAC topics, download our free Home Comfort Resource guide.

Aladdin Heating services Novi, Farmington, Farmington Hills, Southfield, Oak Park, Ferndale, Beverly Hills, Berkley, Royal Oak, Birmingham, Bloomfield Twp., Bloomfield Hills, West Bloomfield, Madison Heights, Clawson, Sterling Heights, Warren, Troy, St. Clair Shores, Grosse Pointe, Grosse Pointe Woods, Grosse Pointe Farms, Grosse Pointe Park, Detroit, Utica, Shelby Twp., Rochester, Rochester Hills, Auburn Hills, Lake Orion, Oxford, and Clarkston.

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