How to install floating floor over hardwood?

[Yuggle]

Hi. I'm installing a floating floor over hardwood flooring (there is reasonable sound-proofing under the floor between the joists) and have purchased Bunnings "Smart Home Products 9.5mm 2.887m2 Soundguard Acoustic Laminate Planks - Camomile". I've also purchased Bunnings "Qep 2mm Ixpe Acoustic Pro Underlay" and several sheets of 6mm villaboard. All up, the 17.5mm is within my 18mm limit for height of the new flooring, and the 2mm underlay is within the requirements of the planks' warranty. My issue is, I'm unsure of whether to install the villaboard first or the underlay first. I'm inclined to install the villaboard first, securely attaching it (not floating) to the wooden floor (the wooden floor is in reasonably good nick, and reasonably flat) siliconing all joins and edges creating a very flat sound barrier. Then install the 2mm underlay then the planks (keeping the sound absorptive layers together). Alternatively, I could install the underlay first, then float the villaboard on the underlay, again siliconing all joins and edges, then the planks. Any thoughts most welcome.

[EricL]

Hello @Yuggle 

Welcome to the Bunnings Workshop community. It's sensational to have you join us and thanks for sharing your question about your floating flooring.

The common sequence when installing floating floor systems is to install the underlay first then the floating floor over it. The underlay provides a cushion for the floating floor preventing it from rubbing against the flooring substrate and creating a squeaking noise when walked on. It also allows the floating floor to expand and retract smoothly during temperature changes. In regards to your own project, I suggest installing the villaboard first to provide a solid base for the floating floor. Installing the underlay first will negate its effectivity as the weight of the villaboard and the floating floor will flatten it. 

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you need further assistance, please let me know.

Eric