2 year old roof - should it have this green stuff?

Old 09-12-20, 05:51 PM
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2 year old roof - should it have this green stuff?

This roof is north facing. It's 2 years old. Installed by an alleged professional but screwed up loads of things.

These are owens corning duration architectural shingles.

Would you do anything about these? It's only in 1 area (which actually sees more light / isn't in the shadow of the house compared to other parts of the roof that are in the shadow / closer to the main part of the house.

When we were turning to owens corning for help about a pro that was listed on their website and did a crap job (fyi - they don't get involved), the question of the Owens Corning warranty came up. They were saying once you pay in full, the pro gives you some paperwork for the warranty. I didn't pay him in full, so we didn't get the papers.

So likely don't have algae

warranty. But this is moss, right?

Wet & forget spray? Power wash? (my wife just came in the room asking what I was posting about the roof. I said 1 of those, she said the other. we were both strongly against the other's suggestion .... and she doesn't know much about house maintenance ; ) Curious if you suggest 1 or the other. Or just leave it alone?

Old 09-12-20, 06:05 PM
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Looks like lichen to me. Best way to help prevent it is by adding zinc strips along the ridge. .....
PJmax voted this post useful.
Old 09-12-20, 06:15 PM
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I didn't pay him in full, so we didn't get the papers.
After two years. ??!!?
So what..... no warranty from the company ?

In my opinion..... a roof should never be power washed.
It's highly destructive even though many claim otherwise.
Old 09-12-20, 06:45 PM
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@pjmax - THANKS! power washing was what my wife offered after I said maybe wet & forget from costco.

She thought chemicals would be too harsh. I knew power washing would strip the granules / do damage.

Yeah, I think we don't have a warranty... which am I too jaded or a realist.... so many caveats . Black algae I think it was, not green,. etc.

What other warranty is there? standing up to wind?

As jaded / suspicious / I'll do it myself as I am, we really got sold good with this guy. He's listed on owens corning site - OH, contractors pay us to be on that list. There's a higher level pro, and those take a course I think it was. And those better ones can sell a better warranty. he was pitching extended warranty sounded like the owens corining warranties / extended warranty that they would have to pay OC for to sell to us. .. .but it would have been his own (since he wasn't in the higher level tier - bascially, he'd come back and fix things - yeah, right... he'd never show if it was needed).

He did a crap job in the end. He got his deposit and nothing else. And yeah, OC was apathetic / we can't get involved in looking at the quality. Oh, they do send out a survey to some people after full payment. So we didn't full pay / they didn't send survey.

Geared to help contractor get paid / not weed out bad apples.

he DID have a great pitch though! 'we;ll clean up all over. sweep with magnetic broom, etc. you find more than 3 nails, we'll come back and do it again''. The fact that he quantified things and spelled out what he;'d do... we liked that. Other guys said 'we sweep / you shoouldn't find nails. give us a call if you do (not saying what they'd do at that point)

We didn't find 3 nails on the ground!! But I went on the roof. I got a WHOLE bag of nails (new AND old), scrap roof material, scrap aluminum flashing scraps, oh, some nails were pressed into the shingles (rather than them step on them and pick it out of the shingles , they left them there!), (shallow) cuts in the shingles - they were cutting other shingles on these? Scuffs / areas with no granules - looked like they were dancing up there, didn't put in a cricket they said tthey;'d put in. Put in a ridge vent over garage... and didn't put in the soffit vents they said they would.

Put in a power roof fan (yeah - power roof AND ridge?) and didn't hook it up.

Put in replacement skylights. had the wrong size delivered. Blamed it on the supplier... but then I remembered he eyeballed the size of existing skylights from ground!

shingles overhang the drip edge / blocks most of gutters about 2 1/2". (standard overhang is 1/2?... interesting - the old roof had that same overhang. I cut then back recently! I can finally clean the gutters without cutting up my hands!

left the ol gutters on till after the roof was on? Then the sub contractor came in prying off the gutter spikes... and potentially damaging the roof?

Oh, and the gutter sub... couldn't pitch 1/2 the gutters correctly. water pooling at the far end on 1/2 of them!

Old 09-13-20, 03:33 AM
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Chemicals will do less damage to the shingles than pressure washing! I've never used Wet&Forget but it has good reviews.

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