You are already well informed!
None of the other companies are willing to talk about it.
Certainteed rep told me directly that they also put 10percent copper coated granules in their shingles
But i know they don’t because i see algae on every roof at year six.
Certainteed even says they warranty algae for ten years.
So i have this customer right now who is contacting me at year 9 1/2.
Very large, steep roof in a nice neighborhood,
He wants to sell his house and is VERY disappointed in how his house looks.
I dont even have to go look.
I know it looks like crap.
Sell your house no later than 5 years if you use Certainteed.
Not much different with the other brands also.
Atlas, Malarky,Pabco for brands that are really trying to keep the algae and streaks off for life.