Ductwork design best practices are necessary to achieve maximum energy efficiency, as well as to provide comfortable airflow with uniform temperatures throughout your home. Rather than relying on rule-of-thumb estimations, you'll want careful planning to design the best duct system for your new home or retrofit. Work closely with your HVAC contractor to meet the following five objectives:
Initial planning
Duct design should be planned from square one with your home design to avoid installation conflicts with building structure, wiring and plumbing. The type of duct materials you choose depends in part on the type and location of the heating and cooling systems you install, energy source, accompanying systems (e.g. zoning and humidification), and the architecture and layout of your home.
Calculating heating and cooling loads
Calculate the heating and cooling loads for each room and total household using Manual J: Residential Load Calculation. The results of the heat gain/loss calculation are needed to correctly size the heating and cooling systems.
Sizing heating and cooling systems
Your contractor should use Manual S to properly size your heating and cooling systems. Systems that are too large cycle on and off frequently, which wastes energy, provides uneven heating and cooling, and imposes unnecessary wear and tear on components. Systems that are too small are overworked, as well, and won’t heat and cool your home adequately.
Sizing the duct system
Additional systems (e.g. zoning, humidification, air filtration, etc.), blower/air handler data and the resulting pressure drop must be factored into heating and cooling equipment sizing for accurate duct sizing. Manual D: Residential Duct Systems incorporates all of these calculations, including room-by-room heat gain/loss, to size your new duct system.
Ductwork installation
Installation best practices for achieving peak heating/cooling performance and home comfort are as follows:
- Compact duct layout through conditioned spaces
- Sealing metal ducts with mastic and mesh; sealing flex ducts with butyl tape
- Balanced air movement through the supply and return ducts
- Correct sizing and location of air outlets, return grilles, cross-over ducts and transfer grills
For more information about optimal ductwork design by a qualified HVAC contractor, please contact us at Hartman Brothers Heating & Air Conditioning in the Fort Wayne area.
Our goal is to help educate our customers in New Haven, Indiana and surrounding Fort Wayne area about energy and home comfort issues (specific to HVAC systems). For more information about ductwork design and other HVAC topics, download our free Home Comfort Resource guide.
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