Unistrut Channel - Materials and Finishes

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Unistrut Channel - Materials and Finishes.


Unistrut channels and fittings offer total flexibility in design and construction of assemblies for framing applications. Unistrut products are available in a range of materials and finishes. These finishes offer differing degrees of corrosion protection for use in a variety of environments. Where required, factory decorative finishes, , are available to order. 


Channels are cold rolled from 1.5mm and 2.5mm steel strip and are available in: 






Mild steel channels are rolled using material formed from BS EN 10025 with guaranteed yield 280N/mm2 and minimum ultimate tensile strength of 370N/mm2. 

Stainless steel channels are rolled using material formed from BS EN10088-2 grade 1.4404 (Grade 316L). Unistrut fittings are pressed from hot rolled, pickled and oiled mild steel plate, or strip steel mainly from grade S315MC OR grade S275 mild steel. Stainless steel fittings are available to EN10088-2 grade1.4404 (Grade 316L).


Hot -Dip Galvanized Channels are Hot-Dip Galvanized in accordance with BS EN ISO1461:2009 and chromate passivated. 

The minimum average Zinc Coating is as follows: 

Cold Rolled From 1.5mm Steel – 55 microns 2.5mm Steel – 55 microns Fittings spun galvanized – 45 microns Pre-Galvanized Pre-Galvanizing is to BS EN 10326 2004 (Coating Z275). 

Stainless Steel 

• Stainless Steel 1.4301 (304) 

• Stainless Steel 1.4404 (316L) 

• Cleaned (Pickled & Passivated) Applying a pickling process to stainless steel results in a clean product and it also removes any heat discolouration that has occurred in the welding process. 

Deep Galvanized 

A deep galvanized coating can be achieved when using steel containing a slightly higher proportion of silicon; for example Corten ‘A’ steel. Silicon bearing steels modify the chemistry of the galvanizing process, resulting in the zinc coating continuing to increase in thickness as long as the steel remains immersed in the zinc. Coatings up to two to three times as thick as the normal standard coating are practical to achieve. 

PVC Coating 

PVC coating is a thick coating with good anti-corrosion properties. It gives a generally good chemical resistance to most acidic and alkaline materials. It is not suitable for use with most solvent based contaminants. PVC coating is suitable for application over hot-dip galvanized steel.

Zinc Electroplated 

Channel nuts and bolts are zinc electroplated


Channels are available in plain or continuous slotted (Code T), in multiple channel combinations and all 2.5mm channels have serrated lips. Slots, 14mm wide x 28mm long or 11mm wide x 25mm long, are provided at 50mm nominal centres. Combination channels manufactured from Pre-Galvanized Steel are spot welded, whilst Hot-Dip Galvanised channels are continuously seam welded or spot welded as appropriate.


Standard channel lengths are 3m or 6m. Cut channel lengths can be supplied.


Weights published in this catalogue for all materials are approximate shipping weights. All dimensions are subject to commercial tolerance variations.


The torque figures stated in this catalogue are based on using a properly calibrated torque wrench with a clean, dry (nonlubricated) Unistrut fitting, bolt and nut. A lubricated bolt or nut can cause extremely high tension in the connection and may lead to bolt failure. It must be noted that the accuracy of commercial torque wrenches varies widely and it is the responsibility of the installer to ensure that proper bolt torque has been achieved


It should not be assumed that the performance of a stainless steel product is similar to that of its mild steel counterpart. 


All part drawings illustrate only one application of each fitting. In most cases, many other applications are possible. Load values are based on use of a PNP12 Unistrut nut and M12 bolt unless specified otherwise.

While effort has been made to ensure the accuracy of the information contained in this catalogue at the time of publication, they cannot accept responsibility for inaccuracies resulting from undetected errors or omissions. 


The standard requires that products are stamped with BSEN6946:1988 and also the name of the manufacturer.

Unistrut® show that the standard is achieved by rolling the channel with the part number along with the full name of the Standard BSEN6946:1988, and also their UNISTRUT® branding.

This is, as it should be, stamped into the Channel to ensure that you can clearly identify their product over the inferior product that is creeping into the market place.

The engraving should also be clearly visible at all times, even when the product has under gone further finishing treatments i.e. Hot Dip Galvanised, Epoxy Coating. Contractors  should be aware of cheap imported and non-standard products that have removable or no product marking at all, as this is not within the Standard.

There is more information about Unistrut full solutions Click Here, or if you would like more information on Unistrut solutions, please contact our technical team on unistrut@dpbuildingsystems.co.uk