Double-slope beam with inverted omega roof slab (Dalla)

The double-slope beam is made of pre-stressed reinforced concrete, with slopes with an incline of 10%. It has a minimum height at the supports – but such that all structural requirements are met – and a maximum height at the midspan.

Its stability during assembly is ensured by a tuning fork constraint at the top of the column, while the lower hinge constraint allows for the handling of lateral forces (possibly produced by earthquakes or wind).

Trave a doppia pendenza con tegolo ad omega rovesciato (Dalla) - Moretti Modular Contractor

The extreme functionality of its slopes, the drastic reduction of unused internal space, the natural solution for water run-off, and the elimination of any type of interfering element (tie-rods or chains) makes the use of this beam and construction system still relevant today.

The double-slope beam with inverted omega roof slab (Dalla) creates a tried-and-tested construction system that offers versatility and functionality, reliability and safety.

Effective structural constraints and minimised construction costs guarantee maximum freedom in the design of industrial or commercial buildings. The dimensional variability of the beam is achieved through the segmented design of the production formworks. With this system, the traditional advantages of the sloping roof are combined with the possibility of large spans of up to 42 m.

The conformation of the beam makes it possible to meet all the fire resistance requirements requested by the customer by adjusting the beam thicknesses.

Holes can be made in the web of the double-slope beam to house the systems network. The relative columns will be prepared to hold the beam, with built-in drainpipes to offer maximum compatibility with different secondary structural elements.

It is possible to include ventilation domes and shed skylights, but excellent illumination can also be achieved by alternating flush solid and transparent elements. Alternatively, opaque roofs can be made from concrete or using sheet metal sandwich panels.

The roof covering can be made of insulated metal sandwich panels or corrugated metal sheets and underlaid insulation. For heated buildings, the roof covering is designed to allow a thermal transmittance of U=0.22 W/m2k.

The double-slope solution can include the inverted omega roof slab (Dalla) as a secondary structural element, which can be laid side-by-side or alternating. The modularity of the inverted omega roof slab (Dalla) guarantees great flexibility, high load-bearing capacity and considerable fire resistance.


  • Large spans up to 42 m
  • Reliability and safety
  • Versatility and cost-effectiveness
  • Easy management of roof rainwater run-off.

Solutions and systems for designers and companies

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