If you cannot afford the official license or simply need a quick reference, use these alternatives. They are not the official ASHRAE database, but they replicate the coefficients from publicly available academic sources and older handbook editions (pre-2013).
The official ASHRAE database contains over 2,000 fittings. Free versions typically have less than 200. For commercial projects requiring SMACNA compliance, pay for the real database. ashrae duct fitting database excel link
The ASHRAE Duct Fitting Database, often referred to as the DFDB, is a comprehensive, electronic database of loss coefficient tables for over 200 different round, rectangular, and flat oval duct fittings. If you cannot afford the official license or
Instead of manually reading complex logarithmic charts (like Chart 14-3 or 14-4 from the 1997 Handbook), the digital database allows engineers to compute dynamic losses instantly using standardized formulas: ( \Delta p = C_o \times P_v ) (where ( P_v ) is velocity pressure). Free versions typically have less than 200
Follow this workflow to set up a dynamic dynamic-loss calculation sheet once your data is linked. Step 1: Set Up the Input Dashboard
) based on geometry and flow rates. Engineers use these coefficients in the standard pressure loss equation:
| Step | Action | |:---:|:---| | 1 | Select the duct function (supply, exhaust, or common) and shape (round, rectangular, or flat oval) | | 2 | Choose the specific fitting type (e.g., 90° smooth radius elbow, R/D=1.5) | | 3 | Enter the flow rate and dimensions (you can toggle between I-P and SI units) | | 4 | Click to obtain the loss coefficient ( K ) and pressure drop (ΔP = K·½ρV²) | | 5 | View results, including a pictorial outline of the fitting with its ASHRAE reference number | | 6 | Export the table data to the clipboard for use in Excel or save to a project (.dfdb) file |