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Floor structural systems

Structural system for the solution of ceiling or floor beams made of thin-walled C sections completed with an array of braces, rods, angle clips and anchor shoes.


The construction consists of a system of thin-walled girders and floor beams supported by traditional steel columns. The columns are typically made of welded square hollow sections (pipes), complete with welded connecting plates for girders, and a base plate.

The girders are fixed to the columns with bolts (at least one pair of them) – via a connecting plate welded to the column. The number of bolts and their specifications are subject to stress analysis calculation.

The floor beams are connected to the girders with bolts via connecting angle pieces. The number of bolts and their specifications, as well as the specifications of the angle piece, are subject to stress analysis calculation. Each pair of floor beams must be interconnected by a stiffening bar (strut) located at the bottom of the section height. This interconnecting bar prevents the section from deflecting under the applied load.

The construction stability is ensured by a system of bracing formed by ties in the planes of the columns and of the floor. In case of the floor plane, the ties are located below the bottom edge of the girders and floor beams. The number and locations of the bracing ties needs to be determined by a stress analysis calculation.

The basic (primary) construction includes a staircase, which can be made as traditional steelwork or the thin-walled version.

In the case of the thin-walled version, the structure is supplemented by connecting components manufactured as a traditional steel structure.

The primary construction is equipped with railings made as a traditional steel structure. For stabilising reasons, the floor structure must be provided with stiffeners at the points of the railing posts, located between the floor beam/girder carrying the railing post and the adjacent floor beam.

The deck is designed from chipboard of a standard thickness of 38 mm, which is supplemented with steel floor gratings. The applicability of gratings is usually determined by fire protection design of the building. Both the board and the gratings must be able to carry the required surface load but must also be assessed in terms of the local loading effects. Since the deck gives stability to the structure, its proper fixing to the girders and floor beams is of great importance. Boards are attached to the structure with self-tapping screws with a diameter of X mm, the maximum spacing between the screws is 600 mm. The floor grating is attached by means of metric bolts with a minimum diameter of X mm and a maximum spacing of 600 mm. If self-tapping screws are used, the load-bearing capacity of the floor beams needs to be reduced by approx. 10%.

Components manufactured as traditional steelwork (i.e. columns, railings or some accessories) or deck components are not supplied by voestalpine Profilform.

The stress analysis and design of thin-walled structures can be done in the Profilform DESIGNER software developed by voestalpine Profilform s.r.o. in cooperation with Idea StatiCa s.r.o. One of the commonly used software packages for the design of steel structures needs to be used for designing the traditional steelwork parts.

A detailed description and design recommendations for different structural components can be found in our METSEC MEZZANINE FLOOR technical manual.


An alternative to floor constructions that are an integral part of the overall system are separately supplied secondary floor beams connected via angle pieces to girders made typically from hot-rolled IPE, HEA, HEB or similar types of section. The floor beams can be designed using our Profilform Designer software, particularly its module for mezzanine floors. Detailed description and design recommendations can be found in our METSEC CONSTRUCTION SYSTEMS FOR SECONDARY STEEL STRUCTURES technical manual.


  • Lightweight and elegant structural solution with high load-bearing capacity
  • Significant weight savings compared to traditional rolled beams
  • Significant cost savings compared to traditional beams
  • Design software for stress analysis calculations and development of production documentation
  • Technical support
  • Easy and fast assembly without the need for heavy handling mechanisms
  • Individual construction components are packed and delivered to the construction site as required by customers.
  • All construction components are individually marked according to customer requirements.


  • 52 sizes of C sections
  • 42 sizes of C+ sections

Example of a section reference code

342M32 = 342-mm-high C section made of 3.2-mm-thick sheet steel

 The range of C sections is marked with letter M in mezzanine systems.

342C+32 = 342-mm-high C?? section made of 3.2-mm-thick sheet steel


All our sections are made of S450GD steel with basic surface protection consisting of hot-dip galvanising with a weight of Z350. If a higher weight of zinc coating is required, we can provide Z600, Z800 or Z1000. The use of zinc coatings of higher than the basic quality one needs to be agreed with us before starting the design work for your structure.


The Profilform Designer software, developed in collaboration with IDEA StatiCa, includes a module for comprehensive design of majority of components of horizontal mezzanine structures, including stress analysis of joints. Special components that cannot be designed by means of our software can be designed in cooperation with our technical support office. 

Stress analyses for systemic mezzanine floors are carried out in accordance with the following standards:

  • EN 1990 and EN 1991-1-1 Basis of structural design and principles and actions on structures
  • EN1993-1-1 Design of steel structures (general rules)
  • EN 1993-1-3 Design of steel structures – cold-formed members and sheeting
  • Designing takes place in line with national annexes.

Designing of production documentation is aided by TEKLA STRUCTURES and ADVANCED STEEL software packages.

Our proprietary METCAM software and a library of details in dwg format are available for users who do not use the above programmes.

To obtain the METACAM installation kit, please contact our sales representatives.