Engineered Wood Floor

[TheScullster]

Hi all

I am considering an "engineered wood" floor in the hall on top of concrete. Is this usually installed as a "floating" floor in this case? If so, how do you stop the floor from floating to one side of the hall (ie moving to take up the expansion gap at one side). My son's room has laminate and it has moved enough to expose the floor edge at the door architrave. Wedging the floor in place would seem to defeat the object of leaving the expansion/float gap.

What sort of underlay stuff is recommended? I used 7mm thick fibreboard under the laminate although this would give a thick overall covering at the door thresholds. Should there be some sort of membrane between concrete and underlay/floor?

Despite attempts to smooth/screed the floor, there is still approx 2mm raise at one door threshold. Will underlay accommodate this?

Are there any recommended web sites giving step-by-step guides for this?

TIA

Phil

[Reentrant]

Friction does the job for ours.

[Tim S]

TheScullster coughed up some electrons that declared:

I'm hoping a heavy engineered floor won't creep, as I'm just about to lay one. Laminate is lighter - perhaps that allowed it to creep?

I'm using this:

top of Marmox board (12.5mm) which is glued down. The foam above has some vapour barrier abilities - so belt and braces with the Marmox which is also a vapour barrier.

A vapour barrier is always advisable. You can use polythene sheet under everything or if not using the fibre board underlay, use something with a built in barrier like the above.

I wouldn't worry about 2mm. I checked my floor with a 6' level yesterday - on "good" screed I'm got 2mm bumps and hollows. It's when you get 5mm+ lumps that problems start showing up with bouncy or creaking floors.

As I'm using Kahrs engineered click-lok flooring I'm going by their PDF instructions.

HTH

Tim

[Roger Mills]

I installed a floating engineered floor in my hall a few years ago, and that hasn't moved.

You can get rolls of the proper stuff - which is 2 or 3 mm of foam, backed by a thin plastic membrane - with the membrane extending beyond the foam on one edge, with a peal-off adhesive strip to achieve decent joins.

Depends whether it's gradual or sudden! The instructions with the flooring which I used specified the max permissible un-flatness in mm per metre. A change in level of 2mm over a metre or so is no problem - a 2mm step would be. I used external grade filler (Tetrion, I think) to achieve the required flatness.

Dunno - but it's much like laying laminate. Remove the skirting boards, and put them back afterwards to cover the expansion gaps. Undercut door-frames, architraves, etc. and slide the flooring underneath - ensuring there's still room for expansion. In a long, thin room, fit the boards along the long dimension rather than across the room. If the starting wall isn't quite straight, scribe the first board to suit, and then use spacers to achieve the desired expansion gap. If gluing the boards together, cramp them up after each 3 or 4 boards, and let the glue set before fitting any more.

All pretty obvious, really . . .

[Reentrant]

... but otherwise have the long dimension facing the main window.