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

This is an AMP page - Open full page! for all features.

• the most efficient way to navigate the Engineering ToolBox!

# Ducts or Pipes through Steel Joists - Maximum Sizes

Maximum duct or pipe sizes through steel joists of K type:

Maximum Duct or Pipe Sizes through Steel Joists of K type
Joists Dept
(in)

Duct or Pipe Size
Round
(in)

Square
(in)

Rectangular
(in)

8 5 4 x 4 3 x 8
10 6 5 x 5 3 x 8
12 7 6 x 6 4 x 9
14 8 6 x 6 4 x 9
16 9 7 x 7 6 x 10
18 11 8 x 8 7 x 11
20 11 9 x 9 7 x 12
22 12 9 x 9 8 x 12
24 13 10 x 10 8 x 13

K series are common open web joists, standard sized for typical applications. K types span from 8’ to 60’ across with depths of 8” to 30”.

## Related Topics

### • Beams and Columns

Deflection and stress, moment of inertia, section modulus and technical information of beams and columns.

### • HVAC Systems

Heating, ventilation and air conditioning systems - design and dimensions.

## Related Documents

### Air Ducts - Sizing

Required duct area vs. air flow.

### Circular Ducts - Dimensions

Standard size of circular ventilation air ducts.

### Duct Velocity

Calculate velocities in circular and rectangular ducts - imperial and SI-units - online calculator.

### Equivalent Diameter - Rectangular vs. Circular HVAC Ducts

Rectangular equivalent diameter for air flows between 100 - 50000 cfm.

### Maximum Floor Joist Span

No. 1 and No. 2 Grade of Douglas fir and maximum span floor joists - imperial units

### Rectangular Ducts - Dimensions

Commonly used metric dimensions for rectangular air ducts in ventilation systems.

### Spiral Ducts - Dimensions

Standard dimensions of spiral ducts - Imperial units.

## Search Engineering ToolBox

• the most efficient way to navigate the Engineering ToolBox!

## SketchUp Extension - Online 3D modeling!

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 Extension Warehouse!

## Privacy

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.