Hush System HF25 Advanced: HD1017

An economical sound insulation system

Hush System HF25 Advanced: HD1017Hush System HF25 Advanced: HD1017

Hush-Felt 25 has been designed as a joist treatment offering an economical alternative to composite floating flooring without compromising on performance. The integral hardboard slats present a firm, smooth surface to support a choice of chipboard, OSB, or plywood T&G flooring boards. 


  • UK Building Regulations Approved Document E New Build compliant
  • A fully developed economical sound insulation system between separating floors for use in newbuild or refurbishment using timber joists
  • Provides a 1 hour fire resistance at ceiling level

Acoustic Performance: 

  • Impact L'nT,w dB - 50 dB
  • Airborne DnT,w dB - 58 dB
  • Airborne DnT,w dB - 52 dB


  • Hush-Felt 25 Resilient Strip stapled to the joist tops, with 18mm tongued and grooved flooring grade chipboard glued above using Hush-Bond
  • 19mm plasterboard plank overlaid with a further lay of 18mm tongued and grooved flooring grade chipboard above, with all perimeters selaed using Hush-Seal 20
  • Hush-Slab 100 fitted between joists with Hush-Bar Plus System screw fixed to the underside of joists at 450mm centres
  • One layer of 19mm plasterboard plank and one layer of 12.5mm Gyproc Soundbloc plasterboard secured to Hush-Bar System. Seal all perimeters prior to skimming


Technical Specifications

Installation Guides