Fishmouthed roof shingle fail(C) Daniel Friedman Early Asphalt Shingle Failure Diagnosis

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Causes of early failures on asphalt shingle roofs:

This roof failure diagnosis article investigates types and causes of premature or early roof wear or failures. We describe shingle granule loss shingle curling as a sign of wear on asphalt shingle roofs and discusses how to identify & explain the most-common asphalt roof shingle failures. Our page top photo shows shingle edge down-curling. Other photos on this page show shingle corner curling.

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Six Year Old Roof Shingle Curling & Granule Loss Diagnosis & Commentary

Fishmouthed roof shingle fail(C) Daniel Friedman Fishmouthed roof shingle fail(C) Daniel Friedman

Question about early asphalt roof shingle failure:

I live in Wisconsin and had my roof replaced (total strip down) about 6 years ago. Now my shingles are curling up or fish mouthing. I do not know what you call it but it looks terrible . Can you help me out? A friend said to check on the internet for something with Owens Corning.

I believe they are 30 yr shingles. I do not have any of the paper work but when they put them on they said they only use premium shingles. Check out the rain gutter. It is 3/4 full of shingle fragments and granules. The rest of the roof shingles still look good. Any help would be great. - Louis Tolley, Adams WI

Fishmouthed roof shingle fail(C) Daniel Friedman Fishmouthed roof shingle fail(C) Daniel Friedman

Answer and advice on diagnosing a failing fishmouthed shingle "new roof" job:

The roof shingle wear pattern in your photos is easily mistaken for "fishmouthing asphalt roof shingle" but what we see in your photos is not "fishmouthing" but rather shingle curling, combined with extreme granule loss.

Comparing Shingle Fishmouth Patterns with Shingle Curling Patterns

Fishmouthing asphalt shingles appear as an upwards curve in the center of shingle tabs, usually where the center of a fishmouthed shingle tab crosses over the shingle butt joints in the course below. See the fishmouth shingle photos above on this page.

Shingle tab curling, such as shown in your photos, occurs at the corners of shingle tabs, not in the center of the tab. See CURLING ASPHALT SHINGLES.

How old is This Roof Wear-Out?

Regardless, your roof photos show severe wear and curled shingle tabs that we see at the end of roof life - your photos of this worn roof slope show that every single shingle tab is curled up from a corner – that combined with the significant granule loss would be very unusual on a six-year-old roof. We comment further and provide some roof failure diagnostic questions just below.

From looking at the photographs, and recognizing that we are not looking at the entire roof, some comments and questions arise that should help sort out this "early roof failure" mystery:

Fishmouthed roof shingle fail(C) Daniel Friedman Fishmouthed roof shingle fail(C) Daniel Friedman
  • The roof slopes in your photographs are totally worn out
  • This does not look like a six year old roof
  • Your comments suggest that other roof slopes are fine.
  • Before we assume that the wear difference is due to the building, roof ventilation, weather exposure, or a similar cause, let's consider that the roof is reported to be just six years old - actually we wonder if that's quite right.

Premature Asphalt Roof Shingle Failure Diagnostic Questions

Watch out: First off - don't fall off the roof while you are up there looking around.

Don't walk on these fragile, damaged asphalt shingles - they'll break and leak.

Go back to look at your information on your 6 year old re-roof job with the questions listed below. If you have no records and no documentation of who did the roof, what was the contracted scope of work (all slopes or just some) we can still figure this out by inspection of the whole building.

  • What type of shingles were installed in your re-roof job six years ago (your photos of failing shingles look like organic base not fiberglass base)
  • Are the same type of shingles present on all roof slopes?
  • Are the shingles that are failing or showing wear the same kind of shingle as on the rest of the roof? Same pattern, model, brand, age, batch, package?
  • Were all the roof slopes re-roofed or just some slopes? Sometimes only the worst or actively leaking roof slope is replaced, especially if the homeowner is squeezing for the lowest re-roof price, money is tight, or the roofer feels that there are five or more years remaining on other roof slopes
  • Did anyone actually inspect the roof before and after the job, other than the roofer?
  • Do all of your roof slopes look the same? That is, is the shingle wear the same on all slopes?
  • Are all roof slopes exposed to similar wind and weather conditions ? Usually not - which slope(s) show the most shingle wear?
  • Are you sure the roofer actually replaced shingles on all of the slopes?
  • Did you actually see that work being done?
  • If you remove or lift one of these bad shingles at the roof edge, do you see raw roof deck below or other old shingle layers?
  • Other asphalt shingle roof wear indicators and conditions (besides fishmouthing) are discussed beginning at ASPHALT ROOF SHINGLES.

Usually when we have inspected early roof failure cases like this it turns out that there was a misunderstanding (or less often, dishonesty) - the roofer did not re-shingle all slopes, maybe just one of them, but the owner thought they all were being done.

Also see our early ridge cap shingle failure discussion at RIDGE & HIP CAP SHINGLES. Readers are also invited contribute roof failure information to the web author for research purposes. web author for research purposes.



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EARLY ROOF FAILURE DIAGNOSTIC QUESTIONS at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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