Uneven shingle installation

Inspected this house yesterday - unknown age of the roof… no apparent permit, but likely 10-12 years old or so. Noted that the rows above the starter course of shingles on most of the roof, front and back are uneven - just 1 row. I can’t figure out how they did this… or why. Regardless, I’m calling for a roofer to evaluate as there is some damage to isolated shingles elsewhere.

I have a carpentry background and don’t know why they did this. It’s not a material defect; maybe aesthetic. The third row up should be measured for excessive exposure.

Even though the shingle overhang appears to be questionable, besides that I see no problem (from photo). The shingle exposure should not exceed the manufactures requirement (of approximately 5 to 5 5/8 inches). The 3 or 4 inch shingle exposure on the second row (course of shingles) was most likely install purposely to reduce damage caused from wind.

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The only reason you normally see that is for spacing of the shingles, if they don’t want to cut excess off at the ridge. But not sure why they would do that at the beginning, unless they actually measured all the way up and did it there instead of at the top.
But it’s not something I would call for further evaluation over

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Non issue here. It’s not uncommon to see uneven shingle courses. Especially if the installer is trying to minimize waste at the ridge. Could have had a rookie doing the installation for all anyone knows… As long as the seal strip isn’t exposed other courses, it functional. I might make a note if it wasn’t consistent all the way around the home, but wouldn’t consider it a “call out” for repair.

There are other issues, some damage to several tabs, etc. That’s the main reason I’m calling it out. This odd spacing is not consistent, one side is larger than the other. One slope doesn’t have it at all…
Just got response from building dept - there IS a permit for the homeowner to repair storm damage… makes a little more sense…

I see no defect there other than poor installation.


If you know how architectural/laminate shingles are manufactured then this is technically a problem. Do you know where the adhesive strip is? On most laminates/architectural shingles, the adhesive strip is actually on the underside of the shingle. The adhesive strip normally sticks to the flat top section of the shingle in the course below for its full length. If you have reduced shingle exposure, the adhesive strip could potentially only stick to the protruding sections of the lower shingle, leading to reduced adhesion between the two courses of shingles, which would reduce the wind resistance of this course compared to normal installation.

Nvm the pictures too slow to upload outside. I’ll do it once I get home

Another reason I did call it out… there were many - probably 20-30% of shingles were loose - didn’t adhere to the course below. Strangely most on this short course were NOT loose, but solidly in place.

When you see a 2’’ course of shingles at the eave, it is most likely a shingle over job. They applied a second layer of shingles over the old shingles, butting the new shingles to the bottom of the old shingles creating a narrow course at the eave.

Expert Tips for Roofing Over Existing Shingles.


Here you go. Like I said, it is technically a problem. Have I personally seen shingles getting blown off because of this? No. Has any shingle manufacturer made a technical article saying don’t do this shit? No, but the required exposure is in the damn installation instructions and on the shingle package.

Do you think when the manufacturer tested the shingles for wind resistance, they let the shingles partially stick together with underexposure? Common sense says no.


I agree with @yzhang however I would not be overly concerned. I would be even less concerned if this was a 3-tab. (By the way Yu, nice photos illustrating the issue)

That makes sense, lump it in with a few other defects to be evaluated or corrected.

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Thanks for all the responses - makes me feel more comfortable in the way I handled it. The buyer was present, with his “I used to build houses” friend… they were upset about this, so I was able to calm them down and still get the issue addressed.