Vertical overspill with concrete hollow core slab

20 September, 2017

Since concrete hollow core slab is getting more and more common, we’d like to spread some information regarding what to keep in mind when planning hearing loops in these buildings. Prestressed concrete hollow core slab is a type of concrete slab with longitudinal cavities/channels. It’s a relatively light-weight concrete slab which lacks the traditional metal reinforcement mesh. When planning hearing loops in building with hollow core slabs, the expected metal attenuation is much less than from the reinforcement in traditional concrete slab floors. Especially the blocking or decreased vertical overspill expected from traditional concrete slab, does not apply to this kind of material. When planning in our web-based tool Univox Loop Designer (ULD), we recommend ”Free field – no metal (0dB)” when choosing the Environment. This will resemble the expected metal impact in a much better way than “Reinforced concrete”. More details here