Said It Here

How to clean dark roof stains without ruining the shingles

Dark roof stains caused by environmental moisture can usually be treated with specialized chemical concentrates instead of a full roof replacement. However, improper cleaning techniques can strip the protective granules and shorten the lifespan of the shingles, leaving homeowners torn between whether to clean now or risk damaging the roof.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Installing zinc strips under the ridge caps
  2. 2
    Using a biocide product specifically formulated for roof and siding cleaning
  3. 3
    Avoiding professional roof cleaning entirely to prevent shingle and granule damage
  4. 4
    Leaving algae and mold alone rather than risking a soft wash
  5. 5
    Using shop towels and a spray bottle
  6. 6
    Installing new plybase

In their words

Unedited, most upvoted first, each linked to the thread it came from.

Not worth it. You will just decrease the life of your roof imo.source ↗

trashbilly · r/Roofing · 4 upvotes

House has a creek in the backyard and the roof shingles are all stained. Are there any chemical concentrates or recommendations for cleaning this to make the color match? Or do we have to replace the roof?source ↗

Fine-Barnacle-1772 · r/Roofing · 1 upvotes

I wish homeownership came with a manual because it is a lot.source ↗

Should I get it cleaned now or hold it off?source ↗

Certain_Temporary664 · r/Roofing · 1 upvotes

Was wondering what the best way of cleaning the surface would be before throwing on the cap sheet.source ↗

Extreme-Ad-6800 · r/Roofing · 1 upvotes

It's my first time, so not super sure on anything haha.source ↗

Extreme-Ad-6800 · r/Roofing · 1 upvotes

I'd never leave it uncovered. Plybase isn't designed to be adhered and not covered same day.source ↗

cgamble718 · r/Roofing · 1 upvotes

Where this came up

People with this problem also raised