# What is an EPS block floor?
**An EPS block floor (Dutch: broodjesvloer, also called a hollow-core slab or beam-and-block floor) is a prefabricated floor system consisting of expanded polystyrene (EPS) blocks placed between prestressed or reinforced concrete beams, then finished with a poured concrete topping layer. The EPS blocks serve as lightweight permanent formwork, reducing the floor’s dead weight while maintaining structural integrity.**
## How it works
Prefabricated concrete beams are positioned at regular intervals across the span. EPS blocks — sometimes called “sandwiches” (broodjes) due to their shape — are placed between the beams, resting on their bottom flanges. Once all blocks are in place, reinforcement mesh is laid over the top and a layer of structural concrete (typically 50–70 mm) is poured, binding everything into a composite slab.
### Key characteristics
– **Lightweight:** EPS reduces dead load by up to 30% compared to solid slabs.
– **Thermal insulation:** The polystyrene provides inherent insulation value.
– **Quick installation:** Prefab beams and blocks allow fast assembly without full formwork.
– **Spans up to 8 m:** Suitable for residential and light commercial use.
– **Flat soffit:** The underside is smooth, simplifying finishing.
## Applications
– Ground floors in residential construction
– Upper floors in low-rise housing projects
– Renovation and extension projects where crane capacity is limited
– Floors over unheated spaces (garages, crawl spaces)
## Related terms
– Prestressed concrete beam
– Hollow-core slab
– Composite floor
– Expanded polystyrene (EPS)
– Structural topping
– Dead load
– Formwork
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