A hollow-block floor is a floor structure in which hollow blocks (blocks of fired clay, concrete or aerated concrete) are laid between load-bearing ribs or beams. The hollow blocks serve as infill and permanent formwork; the ribs between them carry the forces. The floor is lighter than a solid concrete floor and insulates better against heat and sound.
Structure
The floor usually consists of:
- Load-bearing ribs or beams — prefabricated or cast-in-place reinforced concrete
- Hollow infill blocks — laid between them, so that less concrete is needed
- A topping — a layer of concrete over the whole that turns the floor into a composite unit
Application
Hollow-block floors were widely used in housing as ground-floor and upper-floor slabs. They have been partly replaced by the hollow-core slab, the lattice-girder slab and system floors, but still occur widely in existing buildings. When converting, it is important to know where the load-bearing ribs run: openings and heavy point loads should fit the structure. When in doubt, have a structural engineer check.
Related terms
- Floor
- Hollow-core slab
- Lattice-girder slab
- Topping
- Joist floor
- Aerated concrete
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