San Diego Joe wrote:
Pete C wrote:

Derek Broughton wrote:
Pete C wrote:

Derek Broughton wrote:

Millimeters? Not "mils"? Liners in N. America are generally
measured in mils, and a 75 mil liner is thick. If it's really .75
mm, that's 30 mils, and I'd say too thin for an EPDM or vinyl
liner, but not HDPE and _perhaps_ not Butyl. Either way, butyl is
a lot heavier than any of the alternatives at the same thickness.
If it isn't heavier, it isn't butyl.

My 0.75 millimetre butyl liner......
http://www.bradshawsdirect.co.uk/Bra...oduct/GLBU.htm

QED ?

QED what? I'd already discovered that in the UK they were typically
being sold in .75mm, so I have no problem with that, but it's
_still_ much heavier than any other pond liner for the same
thickness. Unfortunately I can't find any actual weights - only the
warnings that they need special shipping, which usually applies to
EPDM, too.

looked for weights too, with no more success than you. As 45 mil
EPDM is in fact 1.14mm thick, wouldn't that be more likely to be the
heavier?


EPDM :
1.02 mm (.040²) 1.25 kg/m2
1.14 mm (.045²) 1.41 kg/m2

from this link:
http://www.firestonebpe.com/lining/s...omembrane/_en/

Interesting that they say the lighter one is recommended for garden
ponds .

They seem to not want to give us the weight of butyl, can't find it
anywhere.

Thanks for that anyway
--
Pete C
London UK