Marmox Australia has announced that Marmox boards now comply with BCA for impact insulation, achieving LnT,w+C1 of 62. They also provide thermal insulation for under floor heating systems. They minimize heat lost in the slab, heat up time and running cost, for nearly the same cost as most acoustic underlay available.
This is good news for architects who specify floor heating in apartment blocks. Field tests conducted on the 10mm Marmox boards by leading acoustic consultant engineers confirmed that floor construction incorporating Marmox boards satisfies the requirement of the BCA for impact sound insulation between sole –occupancy units.
The building was built using load bearing walls and a 170mm slab with resilient mounts and 10 mm plasterboard with a 50mm air gap. The Marmox boards were fixed directly to the concrete bare surface using flexible tile adhesive and the ceramic tiles were fixed directly to the boards using flexible tile adhesive. Although the slab had a ceiling system fixed to it, the structural flanking noise through the four walls in the receiver room minimized the effect of the resilient ceiling construction, which was evident in the measured IIC for the bare concrete slab and resilient ceiling construction of 30.
So in better circumstances (for example, if there was a thicker slab or non load bearing walls), better results could be achieved.