"R D S" wrote in message
...
I'm about to overboard a floor in a flat above a shop, currently tatty
floorboards, going over the top of it with 18mm T&G chipboard panels.

Is there any/much benefit to putting something like this in between?

http://www.ebay.co.uk/itm/261226286963

It will end up with underlay and carpet so i'm wondering if there would
be any benefit.

Everyone uses hardboard to cover tatty floors, this way you don't lose half
the skirtings, an inch of door height or have a top stair an inch higher
than all the others.

Make sure you soak both sides of the hardboard before tacking it down, and
mark the centre of the boards *between* the joists as this is where you need
to fix them, not in line or into any joists, cables, pipes etc...saying that
they only need half inch pins