Proven strategies for getting ducts inside

Builders who adopt the design strategy of bringing ductwork into a home’s conditioned space can more easily achieve state energy code requirements while increasing energy efficiency, and increasing HVAC performance by reducing thermal loss.

Methods and strategies to bring ducts inside the thermal envelope

From the attic to the crawl space, there are a few different approaches to installing ducts in a conditioned space.

• Conditioned attic
  • Fully condition the entire attic or an enclosed space within the attic where ducts are present
  • Ensure there is a complete and continuous thermal and air barrier
  • Make the home’s thermal boundary either the roof plane or the ceiling of an attic room

• Chases, inverted soffits, and dropped ceilings
  • Allow design flexibility and discreet duct placement
  • Good option for single-story homes or when the decision to bring ducts inside takes place after the design is finalized

• Open-web trusses between floors
  • Easy to accomplish in multistory homes
  • Another good option for discreet duct placement

• Crawl space
  • Effective in homes with well-insulated crawl spaces
  • Ductwork must be within the home’s thermal and air barrier
  • Follow local code for unvented crawl space and install continuous insulation on below-grade walls and a Class 1 vapor barrier

Achieve greater efficiency with high-performance building practices

Whether you build homes to the code standard or you aim to go above and beyond, BetterBuiltNW resources, like heat pump design trainings and factsheets on continuous insulation for exterior walls, can help you develop strategies to hit your goals. Get in touch with the team for more information on how to bring ducts inside.