The DFDB is a digital library of pressure loss (loss coefficient) data for hundreds of HVAC duct fittings — elbows, tees, transitions, takeoffs, dampers, and more. It is based on ASHRAE Fundamentals Handbook, Chapter 34 (Duct Design) and ASHRAE Research Project RP-1493.
Whether you are using the modern App or an older spreadsheet, the workflow is identical. ashrae duct fitting database version 60005 free
There is no permanent free version of DFDB 60005, but you may access it at no cost under these conditions: The DFDB is a digital library of pressure
If you already have the database installed: If you already have the database installed:
If you absolutely cannot purchase DFDB 60005, consider these free but less complete alternatives:
| Source | Content | Limitation | |--------|---------|-------------| | SMACNA HVAC Systems Duct Design Manual (3rd ed., PDF sometimes available via libraries) | Tabulated loss coefficients for ~50 common fittings | Static values, no Reynolds correction | | ASHRAE Fundamentals – Chapter 34 (available via preview on ASHRAE website) | Equations and sample tables | Not a searchable database | | Crane TP-410 (free excerpts) | Loss coefficients for basic transitions, bends | No duct-specific tees or branches | | EngineeringToolbox.com | Online calculators for a few fitting types | Very limited set |