[Greenbuilding] experience with Enviroshake?

[abetterbuilder at frontiernet.net]

Quoting Keith Winston <keith at earthsunenergy.com>:

> I don't have experience with Enviroshakes, so I don't know if it's a
> faulty product. But often roofing fails for a reason: wrong
> preparation/underlayment, wrong nailing, installed too tight, etc. The
> most likely thing that I can imagine might curl corners would be
> excessive heat and/or trapped moisture, which would tend to point
> towards faulty preparation.
>
> Lower corners on the shingles should be overlapping the lower course. 
> Trapped moisture should hardly  affect a rubber shingle that far down 
> without affecting the upper part as well.
Any roofing project should be engineered to withstand the high 
temperatures found on roofs.
"Memory" is also unlikely to be a cause, as the shingles were certainly 
cast in their installed shape.
I would suspect that the manufacturer rushed the product to market 
without a long term field test. Lab simulations don't always mimic real 
world conditions.
Bruce Donelson
A Better Builder