Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Ductwork - Supports

Recommended distance between ductwork support hangers.

Sponsored Links

The support distance for ductwork is typical based upon deflection, stress and cylinder buckling analysis.

duct supports

For sheet metal duct work the space between the hangers should not exceed the distances listed below:

Horizontal Ductwork

Ducts SizeMaximum Spacing
(ft, m)
(ft2, m2)
(in, mm)
less than 4 (0.4) less than 5 (125) 8 (2.5)
(0.4) to 10 (1) 5 (125) to 38 (1000) 6 (2)
more than 10 (1) more than 38 (1000) 4 (1.2)

Vertical Ductwork

Ducts TypeMaximum Spacing
(ft, m)
round 12 (3.6)
rectangular 10 (3)
  • 1 ft2 = 0.0929 m2 = 144 in2
  • 1 ft (foot) = 0.3048 m = 12 in

Note! Support systems for ductwork may provide restraint in three directions against displacement and rotation. Consideration must be given with restraining ducts to avoid development of excessive internal duct stresses caused by expansion or contraction due to temperature variations.

Sponsored Links

Related Topics

Related Documents

Sponsored Links

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse!

About the Engineering ToolBox!


We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.


This page can be cited as

  • Engineering ToolBox, (2005). Ductwork - Supports. [online] Available at: [Accessed Day Mo. Year].

Modify access date.

. .


3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Scientific Online Calculator

Scientific Calculator

3 10

Sponsored Links