“Shangles” is the trademarked name Certainteed gives to ALL of their architectural design shingles.
The “Horizon” Shangle is one product I have personal knowledge regarding class action status.
The “Hallmark” Shangle would not surprise me, if it too was in the same legal bind, but I am not aware of that currently being the case.
I am quite familiar with the study regarding color and orientation you provided, and assimilate as many of both, the pros and cons on the side of the argument as I can, if for anything else, at least to expand my own knowledge of the topic, to enable a better judgement to be made for what specifications need to be made for varying conditions.
But!
The manufacturers warranty still takes precedence, (although I am aware of at least one court case which utilized the manufacturers suggestions made via marketing materials, whereby the statements made in that material outweighed the actual written warranty verbage,), so therefor, I still defer to doing things as they are required to be done and then provide additional specifications to exceed those specifications, if I deem necessary.
Ed
P.S. Good discussion though.
P.S.S. After further reading, I would also like to comment that the manufacturers of roofing shingle products and auxilliary materials which work hand in hand, cite that over 90 % of all shingle roofs installed are not installed correctly, therefor negating the manufacturers long-term warranty. There are also statistics compiled by GAF and other sources, that the averager life span of a shingle roof is between 12 years to 15 years. If as they have stated that over 90 % of all shingle roofs are either inadequately ventilated or installed improperly, then the short duration life cycle does not surprise me in the least. This coincides with my 29 years in the roofing trade and 23 years of operating my own roofing contracting company.
Ed