# What is BubbleDeck?
**BubbleDeck is a patented biaxial hollow concrete floor system that incorporates recycled plastic spheres (hollow balls) between the top and bottom reinforcement layers of a concrete slab. By replacing the non-structural concrete in the neutral zone of the slab, BubbleDeck significantly reduces self-weight and concrete consumption while maintaining full structural performance.**
## How BubbleDeck works
The system places hollow high-density polyethylene (HDPE) spheres in a grid pattern between the upper and lower reinforcement meshes. These spheres are held in position by a lattice of steel bars. When concrete is poured, it flows around the spheres, creating a voided biaxial slab that behaves structurally like a solid flat slab but uses up to 35% less concrete.
### Key components
– **HDPE spheres** — Recycled plastic balls, typically 180–450 mm in diameter depending on slab thickness
– **Reinforcement mesh** — Top and bottom steel layers that carry tensile and compressive forces
– **Lattice girders** — Steel trusses that hold the spheres in place during casting
## Structural advantages
BubbleDeck slabs span in two directions (biaxial), eliminating the need for downstand beams in many configurations. The reduced dead load allows longer spans, fewer columns, and smaller foundations. Typical span-to-depth ratios reach 1:30 to 1:35.
## Applications
– Multi-storey residential and commercial buildings
– Parking structures requiring long spans
– Office floors where flat soffits and flexible layouts are desired
– Renovation projects where reducing load on existing foundations is critical
## Sustainability benefits
The system reduces CO2 emissions associated with cement production, uses recycled plastic waste, and lowers transport volumes due to lighter precast elements.
## Related terms
– Hollow-core slab
– Flat slab
– Voided biaxial slab
– Post-tensioned slab
– Precast concrete floor
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