Mildew on new shingles



I have just had a GAF Timberline IR shingled roof installed, but when doing my own inspection I noticed a bit of green mildew along the edges of many shingles and some parts of the roof you can see the discoloration. So much for “Stain Guard” right out of the package (The shingles did arrive on pallets in their packaging). Not all the shingles are like this but many are, perhaps 30%.

Upon further investigation the singles were manufactured in 2012, so they were sitting around all that time (nearly 6 years), and the supplier said it was because not many people in Texas buy hail impact resistant shingles.

I have crawled around the roof and taken 50+ pictures.

The real question is whether this is something to be worried about, or will it all burn off in Texas 100+ degree summer sun? We have no trees shading the roof. Should I press the contractor to have the roof professionally sprayed for mold/mildew? Just throw some Spray & Forget on it myself (is that stuff any good really?) Who is at fault? GAF product, the supplier, or the contractor?

Serious concern or is it one of those “it happens” issues when 200+ bundles of shingles are sent from a warehouse?

Thanks for the help.


As a contractor I would have never accepted delivery of 6 year old shingles. We check all of the bundles when they arrive to make sure lot #'s are all the same. There have been a few times we got shingles 3 years old and we sent them back. After sitting around too long in the packaging the lumps tend to not settle out right after they are installed.

Once algae begins to grow in shingles it does not go away on its own. In intense heat and sunlight it might not get any worse. I would check with gaf and see what they have to say.


Thanks I will contact GAF. I hope I haven’t been taken to the cleaners here, maybe the contractor bought discounted stock, or perhaps just lazy, who knows.

I wonder though, does it sound like they would be ruined or just need work to improve appearance?


Post some pics. However I doubt its that bad that the shingles would be “ruined”.


You do??
What a nightmare!
That is my suppliers job!
I really appreciate my supplier!!
Yes, it is difficult to do.
Many suppliers dont pay enough attention to this detail and they pay hansomely for it…
I left a 10 year relationship with a supplier over this.
They put three different lot numbers on a 50 sq 7/12 Durations.
They refused to pay me a reasonable amount just to fix the front of the house.
They didnt think i would leave over it.


Company I work for has been around for 80 years have been burned many times by many suppliers. Just did a 75k 50 sq 14/12 pig back in October landmark pros, 3 pallets the same 7/17 lot one pallet was 2/15. The branch manager hopped in a truck and swapped it out within hours. All about good suppliers.


Well, in my situation the owner of the roofing company saw the shingles, reported it to the supplier, and they brought another pallet out with instructions to the foreman to discard anything that looked bad.

By the end there was a huge pile of discarded shingles (a pallet worth). It wasn’t very confidence inspiring, but then again, I’m glad they didn’t just put that pile on the roof. It seems like they were trying to do right?


Sounds like they were both trying to do the right thing. If a supplier told me to sort through shingles I would tell them to pound sound. The roofer used alot of labor doing that, I give him credit.


Thanks, that helps my confidence. I figured I should give them the benefit of the doubt here, because there seemed to be a concerted effort to make it right.