Westok Cellular Beams


Cellular Beams

Cellular beams are the modern form of the traditional Castellated Beam. Westok cellular beams comprise a beam formed by profiling a rolled section using our patented, semi-circular dual pass process.

The two tees are separated by half a pitch and the beam is welded back together. The resulting cellular beam has a continuous string of circular or elongated cells along the full length of the beam.


Uses and Applications

The Westok Cellular Beam is used in applications where there is a requirement to achieve one or more of the following:

Economic clear floor and roof spans

Shallow downstand floor beams, where rolled sections have insufficient capacity

Service integration and/or assistance with the building ventilation strategy by utilising the cells within the depth of the beam

An aesthetic exposed structural steelwork solution

Flexible Profiling Process

There are essentially an infinite number of possible cellular beams which can be formed in depths of 1mm increments. The overall beam depth, cell diameter and spacing can be tailored by the designer to best suit the application.

Top and Bottom Tees

The top and bottom tees are frequently cut from different rolled sections, with the resulting asymmetric Westok beam formed with each tee/flange designed to suit the load it resists and the restraint conditions which apply locally.

This is particularly beneficial in composite construction, where the concrete slab resists most of the compression in the composite beam. This permits a much smaller and lighter top tee to be used. Also, where lateral torsional buckling of either flange is the key design check, the tee can be sized appropriately to suit.

Cut-Down Cellular Beams

A cut-down Westok Cellular Beam is used when the designer faces an onerous depth restriction and cannot use a traditional rolled section as it has insufficient capacity.

Frequently depth restrictions require engineers to design shallow floor beams to span long distances and to carry heavy loads. The overall depth of the Westok beam is shallower than the parent section, however the beam has significantly enhanced section properties compared to a rolled section of equivalent depth.

To aid this process, the Cellbeam software package can be used to design an automated beam of fixed depth to match the restriction faced by the designer.

Curved and Tapered

Minor modifications to the profiling process can allow curved and tapered beams to be manufactured.

Curved and tapered Westoks are very popular applications of our beams.

Profiling Process

The patented profiling process leads to a beam with a continuous string of cells along the full length of the beam. The beam is therefore, very flexible in terms of the provision of cells for service integration.

Elongated cells can be readily provided where there is a requirement to pass rectangular shaped services through the beam.

As the entire beam comprises web penetrations, there is much freedom to accommodate changes/additions to the future service integration needs.


The continuous string of cells is also beneficial in assisting the ventilation strategy of the building, where the web penetrations maximise the potential for air-flow through the beam.

Other Westok Products

Ultra Shallow Floor Beam

We have developed and patented an innovative and economical  ‘flat-slab’ flooring system – USFB®



Other Westok Products

Westok Plate Beam

Our Westok Plate Beams are manufactured using advanced welding technology on our submerged-arc T & I line.

Get in touch with us

We would be happy to help if you have any questions or queries, please get in touch.

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