What happens if you mix algae resistant asphalt shingles with non-algae resistant asphalt shingles?

Question

Is there a reason for this?

Answer 1

Two things will happen.  The shingles that are not algae resistant have a better chance in obtaining algae.  Secondly, these two shingles are from different lot runs and will probably have some slight variation in color and appearance.  good luck.

Answer 2

Your house will explode!!

Answer 3

If the color match is acceptable use the algae resistant ones on one side, (preferably on the north facing sides), and the non resistant ones on the other. Or, install the algae resistant on the top half and the non resistant ones on the lower half. This would allow the chemicals to wash down on too the non resistant shingles, giving some protection. Don't sweat it, either way. The resistance is not forever, and its possible, you may never notice the difference. You can also buy zinc or copper strips, that you can use to supplement the protection. See a roofing supplier for these, and how to use them.

Answer 4

nothing, u just void the warranty of the roof.....

lic. gen. contractor