HeyBub wrote:

Tim Watts wrote:

If moisture IS present, you install a "vapor barrier' - essentially
plastic film - before installing the laminate underlayment then the
actual flooring.

If there is NO moisture found after the test, you can dispense with
the vapor barrier, although it certainly won't hurt to have one
anyway.

Agree - the cost of a sheet of plastic is peanuts in the grand scheme.

I don't think it's EXACTLY peanuts. Vapor barrier material may be as low
as five cents/sq ft (impregnated paper) up to, if it includes cushioning
underlayment, up to $0.90/sq ft.

Note there is NO difference between a vinyl vapor barrier and 6 mil
contractor trash bags. With the latter, you'll do a bit more cutting and
taping. That's all.

If you're paying say $2/sqft for a decent laminate (Pergo say) or $4+ for
engineered harwood (Kahrs), it would be really cheap to worry about 10c/sqft
for a vapour barrier

Or you can use roofing felt, which is probably the easiest to install and
pretty cheap ($0.11/sq ft from HD).

Felt - that's just pikey...

But as you say, many underlays are available with inbuilt vapour barriers -
it's what I used - and an underlay on concrete is a good idea unless you are
going to glue the boards down - get's rid of the "hardness" of the surface
and makes it much more pelasant to walk on barefoot.

--
Tim Watts Personal Blog: http://www.dionic.net/tim/

"History will be kind to me for I intend to write it."