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Carpets, Lino & Flooring

Floor insulation over chipboard & directly under vinyl planks

Anonymous user 28/02/2024 - 3.33 PM

Looking for advice on insulation (rolls/boards) to be used over chipboard subfloor (ground floor) and ideally as a direct base for laying glued vinyl planks. (Likely Moduleo floor) The room is ground floor/suspended floor and it's about to have new joists/chipboard installed. I'm hesitant to put anything between the joists because we previously had problems with damp cavity wall insulation and it has put me off filling any intentional void areas (i.e. between and under the joists). I do not want to glue the vinyl planks directly to the chipboard and am hoping I could install some (thin) insulation on top that would add an extra moisture barrier to the chipboard, prevent some cold from rising from the void beneath. I'd like to skip adding a plywood layer prior to the vinyl plank installation and use the insulation layer as the base for the glue instead (due to cost + the moisture/heat benefits that would come from the insulation instead of ply). Is this possible and are there any recommendations of types of floor insulation I can use as described above? It would need to be sturdy enough to avoid the planks bending/creating dents under the heavy weight of wardrobes.

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3 Answers

Inspired Floors

Rating: 5 out of 5

Ramsgate

your only real option here is to insert insulation between joists. then overply the chipboard with flooring grade plywood. then fit your moduleo floorcovering. this will prevent denting. the only insulation you could stick to otherwise is jumpax, and thats a 2 part system but wouldnt be as cost effective. Do it right the first time rather than try to cut corners, and youll only pay once and have no problems with your floor

Answered26 December 2017

Anonymous user

The easiest and best way is to fill with polystyrene as this can't hold the wet at all. It usually comes in 1,2 and 4" thicknesses and sizes are usually 4' x 8'. You can cut them with a normal handsaw but it squeaks like nails on a blackboard! You can get various underlays that can sit between joists and flooring, ranging from thin plastic sheeting known as damp proof membrane to layers of polystyrene as mentioned. The people doing the flooring should know the best method and advise accordingly. Filling between the joists would be as simple as nailing battens to the underside of the joists, cutting the polystyrene to the correct width and dropping them in place. Normally though, the floorboards just go on top of the joists and that's it.

Answered12 December 2017

cmw floors and wetrooms

Rating: 4.9 out of 5

Frinton On Sea

Once the joists are installed, lay a mesh over the top of each, but allow to droop, between each, to lay insulation in, (Celotex or rockwool), then go over the top with PLYWOOD, absolutely avoid Chipboard. Then once skimming the joints, etc, you can stick your flooring direct to that.Hope this helps, have done it in the past with great success, Chris M-W.

Answered23 June 2021