There is a lot of malware-ridden "cracked" software floating around HVAC forums. Do not use those. ASHRAE provides the installer for free, but they require a quick registration. Why? Because version 6.0 is technically "retired" (v7.0 exists for paying members), so they unlocked v6.0 as a public service.
License activation: Enter your 25-character license key (emailed upon purchase). For membership-based access, log in with your ASHRAE credentials.
Integration step: During installation, you will be prompted to select which CAD/analysis tools to integrate. Check the box for any software you use (e.g., Revit 2022-2024, Trane Trace 700, Carrier HAP).
Complete installation: Click Finish. The database will launch a configuration wizard to test connections to Excel and your chosen HVAC tools.
Post-install update: After first launch, go to Help > Check for Updates. Version 60.1 (a minor patch fixing rounding errors in oval ducts) may be available.
If you need the full, activated version of the ASHRAE Duct Fitting Database Version 6.0, you must acquire it through the official ASHRAE Bookstore.
Installation Steps:
If you are a student or a professional who cannot afford the full database, ASHRAE provides a very useful free resource that utilizes the same data.
The ASHRAE Duct Fitting Database Application (Mobile/Tablet): ASHRAE offers a "Duct Fitting Database" application on mobile platforms.
PDF Resources: While not the interactive software, the raw data for duct fitting loss coefficients is available in the ASHRAE Handbook—Fundamentals (Chapter 21: Duct Design). Many university libraries provide free digital access to the ASHRAE Handbooks for students.
The true power of DFDB v60 is its ability to export loss coefficients directly into HVAC load/design software.
Version 60 includes over 2,100 fittings—nearly 15% more than Version 5.0. New additions include:
You are allowed to use this for commercial work. However, you cannot redistribute the DFDB_60.mdb (Microsoft Access database) file to colleagues. Point them to this guide so they get their own clean, virus-free copy. There is a lot of malware-ridden "cracked" software
Have you run into installation errors on Windows 11? Drop a comment below with the error code, and I’ll help you troubleshoot the registry fix.
Disclaimer: This guide is for educational purposes. Always verify coefficients against the current ASHRAE Handbook. I am not affiliated with ASHRAE, Inc.
ASHRAE Duct Fitting Database (DFDB) Version 6.0 is a specialized engineering software designed to calculate pressure losses in HVAC duct systems. While many online searches target "free download full install" versions, it is important to note that the full Version 6.0 is a proprietary, paid product traditionally sold by ASHRAE on CD or through a cloud-based subscription. Google Books Overview of Version 6.0
Version 6.0 represented a significant update to the tool, introducing an integrated database and dynamic calculations that update in real-time. It provides loss coefficient tables for over 200 round, rectangular, and flat oval duct fittings Core Functionality
: Users enter flow rates and specific fitting parameters (e.g., width, height, radius ratio) to obtain precise loss coefficients and associated pressure losses. Key Features Pictorial outlines of each fitting for easy identification.
Project management tools to save, navigate, and transfer fitting data into project files. Support for supply, exhaust, and common duct functions. Full compatibility with both I-P (Imperial) SI (Metric) Google Books Access and Official Versions ASHRAE currently offers the database primarily through a cloud-based annual subscription Integration step: During installation, you will be prompted
. While Version 6.0 was once distributed as a standalone CD-ROM product for single users, the industry has moved toward more flexible mobile and web options. Duct Fitting Database Lite App
mobile alternative for iPhone and iPad. It allows for quick field calculations using a subset of the most common fittings (approximately 14) from the ASHRAE Handbook. Full Mobile App
: ASHRAE also offers a paid mobile version (v6.1) that includes the complete library of 250+ fittings and allows for report sharing via email. Official Purchase
: The full desktop/cloud version can be acquired through the ASHRAE Bookstore Implementation and Support
For professional use, the database is often linked to larger duct design programs to streamline system-wide pressure drop calculations. Users of the standalone Version 6.0 often require Adobe Acrobat Reader
to view technical help documents and loss coefficient PDFs within the software. If you need the full