Geoplast Insights

Voided slabs’ benefits

Voided slabs are significantly improved versions of solid slabs and offer more improvements for the building as a whole. They consist of two thin slabs and ribs connecting them, having the same or better performances than a solid slab, with less concrete used.

Structural benefits

  • They weigh less, making the whole building structure more seismically resilient,
  • They don’t need beams,
  • The foundations are less stressed because of the decreased construction load,
  • Are suitable for medium to large spans (7 – 12 m),
  • Even voided, these slabs have the same strength as solid slabs.

Functional benefits

  • Voided slabs are suitable for spaces with irregularly positioned columns,
  • Larger spans offer higher flexibility of interior space organization,
  • Flat lower surface provides uninterrupted passage to conducts and pipes,
  • Improved aesthetics for flat and smooth ceiling surface,
  • Easier further processing, plastering, or mounting of suspended ceiling.

Economic benefits

  • Use of plastic formwork embedded in concrete slabs decreases the concrete volume used (up to 20%),
  • They save costs and time speeding the construction process.

Environmental benefits

  • Decrease of concrete used impacts the amount of CO2 emitted in the air.

Our products New Nautilus and New Nautilus Evo are used for voids in bidirectional slabs. They are used as single or double elements, increasing the depth of slab when necessary. Approximate thickness of slab is calculated as L(span) / 28. Our Airplast is used for voids in monodirectional slabs, and in prefabrication of predalles slabs.

All our slab formworks are easy to use, transport, and stack, and make the buildings more resilient and sustainable. We have also designed calculators for slabs dimensioning, which help engineers to take real slab thicknesses in the early phases of the design process.

Voided slabs projects

Marmara Tower, Turkey

Santo Stefano hospital, Italy

Ericsson Italy Headquarters

Varyant Tower, Turkey

Research center EDF, France

Antica corte, Italy

Learn more

New Nautilus
New Nautilus Evo
New Nautilus slabs calculator
New Nautilus Evo slabs calculator
Airplast
Slabs solutions