Steel Hollow Sections: What is CHS, RHS and SHS?

February 17, 2022


Steel hollow sections, otherwise known as structural steel tubes, are categorised into three main types: RHS (rectangular hollow sections), SHS (square hollow sections) and CHS (circular hollow sections). Also referred to as Box Steel, Square Steel, Tube Steel or Rectangular Steel tube, hollow sections are commonly used in welded steel frames where forces are experienced in multiple directions. Steel hollow sections boast uniform strength thanks to their uniform geometry, making them ideal for columns and posts.

For this reason, residential construction heavily features the use of steel hollow sections. Many homes use these posts without you even knowing! Because of their size, they can be effortlessly disguised in materials to match the aesthetics of your home.

To learn more about steel hollow sections and their differences, keep reading for everything you need to know about CHS, RHS and SHS.

CHS – Circular Hollow Sections

Circular hollow sections (CHS) was the first form of hollow section and are still commonly used in a wide range of structural, mechanical and construction areas. Its uniform design gives CHS tremendous resistance to torsional forces.

Thanks to its clean, consistent lines, lack of protruding edges, and smoothness of CHS make it a popular architectural choice for aesthetic appearances in various applications. The lack of protruding edges also reduces the impact of exposure, dust and other material build-ups. However, keep in mind that CHS tubes are typically more expensive than their RHS and SHS counterparts.

RHS – Rectangular Hollow Sections

Favoured for mechanical, structural, and construction applications, Rectangular hollow sections (RHS) feature flat surfaces that are more economical for joining, alongside various other types of fabrication works. Thanks to the flat surfaces, only a straight cut is required for joining, with minimal edge preparation needed for welding or joining, giving it clean lines alongside structural strength.

SHS – Square Hollow Sections

Sitting comfortably between RHS and CHS, Square hollow sections (SHS) strike a balance between appearance and strength. Much like RHS, an SHS features a flat surface, making it more economical for joining and welding, with clean lines and minimal edge preparation required.

SHS is most commonly used in constructing entry porches to support the roof. The steel is then covered in brickwork or timber to match the house.

If your job requires a professional touch, give Steel Builders a call. We're always looking for newer and smarter ways to make building and construction easy and more efficient. Our highly experienced steel fabricators use high-quality steel products to meet Australian Standards. Shop online or Get a quote for your next project today!


Leave a Reply

Thomas P
I believe in making the impossible possible because there’s no fun in giving up. Travel, design, fashion and current trends in the field of industrial construction are topics that I enjoy writing about.


Welcome to Urban Splatter, the blog about eccentric luxury real estate and celebrity houses for the inquisitive fans interested in lifestyle and design. Also find the latest architecture, construction, home improvement and travel posts.


© 2022, All Rights Reserved.
linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram