WF (Wide Flange) steel — often called an I-Beam because its cross-section resembles the letter I — is the most widely used structural profile in steel construction. Its tall, slender shape delivers high bending strength with minimal material weight. Here are the six applications we supply most often.
1. Warehouse and factory roof frames
WF is the go-to choice for wide-span roof trusses and girders. Its large moment of inertia lets a single member span long distances without intermediate columns — ideal for warehouses, hangars, and industrial buildings that need open floor space.
2. Floor beams and mezzanines
As floor beams, WF carries live loads from floor slabs and transfers them to columns. The profile is also common in mezzanine structures — added floors inside warehouses or shophouses.
3. Structural columns
For columns in low- to mid-rise buildings, larger WF sizes (e.g. WF 350 × 350 and up) carry vertical compression loads. For heavy loads from all directions, H-Beam is often more suitable — we cover the difference in our WF vs H-Beam article.
4. Bridge structures
WF is used as bridge girders for short to medium spans, including pedestrian crossings and access-road bridges. For these applications, higher-yield grades such as SM490 are often specified.
5. Industrial supports and platforms
In plants and refineries, WF forms pipe racks, access platforms, and equipment support structures. Its stiffness keeps deflection small under dynamic loads.
6. Crane runways and frames
Large WF sections are used for crane runway beams — the rails an overhead crane travels on — as well as the posts and portals that carry lifting loads. Controlled deflection is essential for smooth crane travel.
Choosing grade and size
For structural work, what matters is not only the size but also the steel grade — SS400, SM490, or equivalent — which sets the yield and tensile strength. See our technical reference for mechanical properties and chemical composition by grade, and the full WF specification tables for dimensions and weight per size.
Always follow your structural engineer’s calculations — our tables are a starting guide only. Need a specific WF grade or size? Contact the Marselus Steel team — we have served clients since 1996.
