Originally Posted by tj_ras
2l and 3l explained
Incase you would like to read more.....if you dont want to read the whole article, its on page five, just scroll to 2lvs3l.
Whole article talks about different systems along with pros and cons, ie: goretex,eVent, pu, etc. etc.
I felt it was a good read.
Little excerpt from the article, to possible spark your interest.
What they wrote is sort of true - in reality it really depends on the type of (separate) lining used in the 2L fabric. Some brands do stupid things like using linings that interfere with the breathability (some of the insulation in non-shell jacket is also terrible - really no point having a membrane in that case).
In practice, as long as the lining is not terrible there is no difference in breathing or waterproofing performance between 2L and 3L.
Also, some people do not like the 'stiff' feel of the 3L laminate.