Inverted omega roof slab (Dallone)

The inverted omega roof slab (Dallone) for flat roofs is produced in heights of 40 cm, 60 cm and 80 cm and has a lower layer with a modular width of 250 cm with a thickness of 10 cm and 15 cm, which houses the prestressing strands. The inverted omega roof slab (Dallone) can be produced in widths smaller than the modular 250 cm and with variable lengths up to 27 m, depending on the specific project requirements, within the limits of structural feasibility. This means the system offers ample flexibility in terms of size.

The inverted omega roof slab (Dallone) is designed for high working loads usually between 5 kN/m2 and 30 kN/m2.

Tegolo ad omega rovesciato (Dallone) - Moretti Modular Contractor

The inverted omega roof slab (Dallone) can be laid in combination or interposition with compensating slabs. The cavity on the extrados of the slab is closed with a fretted metal sheet that then serves as disposable formwork for creating the structural screed, with a thickness varying from 5 cm to 15 cm, which, in addition to enhancing the mechanical properties of the system, also serves the function of load distribution and holding together the overall structure.

This creates an arrangement of closed sections in the roof, which provides it with excellent torsional resistance to counteract the effects of even very heavy point loads.

The inverted omega roof slab (Dallone) features high load-bearing capacity and considerable fire resistance, insofar as, as compared to other types of roof slab, it minimises the surface area exposed to the fire, which protects the prestressing strands from high temperatures. It has been researched and designed to reduce the weight of the roofs it is used for, thereby reducing horizontal seismic actions and vertical actions, with the aim of reducing the dimensions of the foundations.

The shape of the slab makes it easy to insert the holes required for the interface with the building installations.


  • Very high static performance and fire resistance.
  • Great torsional resistance of the roof.
  • Flexibility of structural composition.
  • Easy creation of holes for building installations.
  • The inverted omega roof slab (Dallone) creates the lightest and highest-performance roofs on the market (for the same spans and working loads).

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