DECKfon acoustic overlay treatments are created for conversion projects where the joist is covered with a timber decking and the ceiling is to be changed. In addition, the boards can be used to lower the impact of sound transmission through a concrete floor. DECKfon soundproofing overlay boards come in three thicknesses 17mm (17T), 26mm (26T) and 30mm (30T). All of the boards have been created to expand sound proofing performance of existing timber floors in a refurbishment development. Boards are installed on top of a timber sub-deck, laid on timber floor joists. The properties of the DECKfon acoustic overlay include a tongue and groove edge detail. The board size comes in 1.44m2 and the overall weight in 13.4kg per m2.