These days, more attention is given to energy efficiency and comfort in newly-constructed homes and retrofits. If your home is older, it’s possible that the duct system design was cookie-cutter style (quick and easy), rather than designed specifically for long-term energy efficiency. If you’re planning construction or retrofit, it’s important to know the elements of good duct system design.
Three elements for duct design
Efficient duct system design enables all other home-comfort systems to reach maximum efficiency. With so much riding on duct performance, it’s critical to get these three elements of duct design right: layout, installation and circulation.
Layout: For the least restrictive air flow, ducts should be designed to take the straightest, shortest path from the blower to the living space. Duct returns should be located on each level in multi-level homes. For greatest efficiency, small duct returns should be located in all rooms with air-supply registers.
Installation: Used smooth, curved turns rather than sharp, right-angle turns. Installing ducts in unconditioned areas should be kept to a minimal. Unconditioned areas are magnets for energy waste. If you must utilize these areas, insulate the ducts. Decrease the size of ducts over distance. This maintains air pressure. Joints, air-supply registers and return grilles must be sealed tight to prevent leakage.
Circulation: Neutral air pressure is important for keeping your home sealed. Variances in air pressure due to poor duct design encourages, or forces, air exchange between your indoor air and outdoor air. Measurements for air supply/return should be made by a reputable heating and cooling professional.
Poor duct design signs
It’s relatively simple to recognize poor duct design. Look for these clues:
- Uneven temperatures in the home.
- Uneven pressure from the registers.
- Noisy ducts/registers.
- Disconnected duct joints and damaged ducts.
- Ducts in unconditioned areas with no insulation.
For new duct construction or retrofitting, it’s important to work closely with your contractor to ensure energy savings and comfort for years to come. Contact us at Donald P. Dick Air Conditioning. We’ve been helping homeowners in the Fresno area make the best choices for their individual needs since 1970.
Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about duct system design and other HVAC topics, download our free Home Comfort Resource guide.
|Energy Efficiency image via Shutterstock|