Underlay & Suspended Floor

[Séan Connolly]

If I use something like this as an underlay for laminate floor:

is it still worth covering the suspended floor with a hardboard covering to iron out any unevenness in the floorboards ?

Ta

Séan

[Tim S]

thick and will absorb minor irregularities, especially slight steps between floor panels/boards. You could add a course of the 2mm foam underlay too if needed - tack it down with a staple gun. Leave small gaps (1-2mm) betweeen the green slabs. Not critical but this stuff does expand and contract too, basically don't pack it tight in.

Do check that you haven't got any major undulations or low/high spots with a 2-3 metre straightedge on the subfloor before you start:

I didn't and I had to insert packing around a doorway after the fact which worked out OK, but less than perfect - if I'd noticed I'd have considered levelling compound first. This was due to a floating floor where the chipboard was sitting on expanded plastic slabs which had compressed over the decade around most doorways. The depression was about

5mm-7mm over a metre or so, not enough to see, but enough to form a hollow under the laminate. Laminate can follow gentle undulations, but not that extreme.

Have I ever said that some modern building practises are the work of the devil? Floating subfloors and drywalls - lazy, cheap and evil.

HTH

Tim

[Séan Connolly]

Thanks for the insight Tim. Upstairs I'm fine, downstairs, both reception rooms have a pronounced hump in the middle. I guess the easiest way to get around this is to rip out the floorboards and replace with chipboard.

Having had to replace a few lath & plaster ceilings and walls I'd argue that they were the work of at least a minor evil diety !

[Tim S]

That's fair. L&P ceilings are a pain to fix.

I was thinking of solid walls (especially if brick) and floors with 8" joists - much better.

Tim