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Steel colour coding: size guide

Steel colour coding can be confusing, so we’ve put together two helpful guides to ensure you understand how to interpret our steel colour coding. 

We’ve even included a PDF document for you to download and keep at the ready.

While we endeavour to be as accurate as possible with our steel colour coding, we always recommend checking the thickness and/or diameter of your product before commencing steel works. 

This month we are focusing on the colour codes relating to thickness.

Make sure you check out next month’s guide on colour coding that identifies the grade of material.

Steel colour coding for thickness

Thickness refers to the thickness of the wall for square hollow section (SHS), rectangular hollow section (RHS), and circular hollow section (CHS; pipe) products. It also refers to the thickness of a flat bar, equal or unequal angle and square bar.

Diameter refers to the diameter of a solid round bar or reo bar. 

Colour refers to the colour of paint that we’ve applied to the end of the steel product. 

Signet code (name and number) is the paint manufacturer’s unique name and product code. This helps to ensure that we apply the same and correct colour paint to our material each and every time we receive a new stock delivery.

Colour-coded products

We use our steel colour coding (for size) on the following Edcon Steel products:

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