On Fri, 18 Sep 2009 16:45:46 +0100, Dave Plowman (News) wrote:

But the stairs I'd use something thinner, they take quite a
pounding
and all the movement that a thick underlay will allow in the
carpet
won't do it any good IMHO.

Surely the whole idea of an underlay is to allow the carpet to move
relative to the floor?

Move a bit but not too much otherwise the movement causes the threads
to wear against each other. The major factor is the amount of
traffic, high traffic areas like hallways and stairs just need a thin
underlay to buffer the carpet from the hard floor and to allow some
relative movement. Low traffic, like a bedroom, you are more
interested in comfort and as it's low traffic can tolerate more
movement to get you the higher comfort.

--
Cheers
Dave.