Ashrae Duct | Fitting Database Excel

The ASHRAE Duct Fitting Database (DFDB) is widely considered the gold standard for HVAC design engineers needing accurate loss coefficients for round, rectangular, and flat oval fittings. While originally known for its standalone software, its integration with Excel workflows remains its most practical application for modern professionals.

Covers supply, exhaust, and common (supply/return) duct functions. ashrae duct fitting database excel

With coefficient C , velocity pressure Pv (in inches w.g. or Pa), the loss is: The ASHRAE Duct Fitting Database (DFDB) is widely