About those (ridiculous) Tyvek videos...
There are no industry accepted laboratory or field tests for water leakage through non-glazed walls, nor are there any failure criteria established for such testing. This is for the good (and obvious) reason that individual components of a wall assembly cannot be evaluated independently of their context within the rest of the assembly, nor can a wall assembly be evaluated independently from its climate (exterior and interior) and exposure.
Performing a test intended for windows on incomplete portions walls -- with no cladding, and none of the thousands of cladding fasteners typical of the most popular cladding systems -- and attempting to derive anything meaningful from the effort is beyond ridiculous, especially when it is absolutely indisputable that both products being evaluated in these videos have a long history of in-service performance in countless configurations.
The "water column" test of an overdriven fastener is even more egregious. About this test, DuPont had the following helpful comments, which appear near the end of the video:
Performing a test intended for windows on incomplete portions walls -- with no cladding, and none of the thousands of cladding fasteners typical of the most popular cladding systems -- and attempting to derive anything meaningful from the effort is beyond ridiculous, especially when it is absolutely indisputable that both products being evaluated in these videos have a long history of in-service performance in countless configurations.
The "water column" test of an overdriven fastener is even more egregious. About this test, DuPont had the following helpful comments, which appear near the end of the video:
Allow me to translate: We decided to compare the perfect installation of our product with the imperfect installation of our competitor's product and, since no standard exists for this kind of thing, we decided on the equivalent of a Category Five hurricane force wind continuously... for five hours.
(Indeed, 55 cm = 21.65 in, which equates to about 112 psf, or an approximately 212 mph wind. Maybe they thought if they used metric it would seem less stupid?)
These videos tell you literally nothing about the real performance of the products in question, but they tell you a great deal about what DuPont thinks of their customers.
Next: What about structural strength?
(Indeed, 55 cm = 21.65 in, which equates to about 112 psf, or an approximately 212 mph wind. Maybe they thought if they used metric it would seem less stupid?)
These videos tell you literally nothing about the real performance of the products in question, but they tell you a great deal about what DuPont thinks of their customers.
Next: What about structural strength?