Ribbed and waffle slabs provide a lighter and stiffer slab compared with an equivalent flat slab, reducing the extent of foundations. Providing a very good form of construction with less vibrations.  Ribbed slabs has wide band beams running between columns with narrow ribs spanning the orthogonal direction. Both of them are having the same depth. A thin topping slab completes the system. Waffle slabs tend to be deeper than the equivalent ribbed slab.They have a thin topping slab and narrow ribs spanning in both directions. The column heads or band beams are actually the same depth as the ribs are. The benefits of using this type of slab are: flexible, relatively light,  (therefore less foundation costs and longer spans are economic), speed of construction, fairly slim floor depths, robustness, excellent vibration control, thermal mass, good for services integration, durable finishes, fire resistance.

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