Wow, I am late on this. By a few years…
Yes, downspouts discharging onto lower shingle roofs is bad. I think I saw other posts with photos of the damage that is caused over time.
In addition, it absolutely deviates from the Code requirements. Where does it say that you ask?
If you all remember, every version of the Code requires that all materials and equipment be installed in accordance with the product manufacturer’s installation instructions. Go read or call and ask if the shingle manufacturer is OK with gutters discharging onto a lower shingle roof. Not sure who made the shingles, try any of the large national manufacturer’s. they all same the exact same thing.
They are not OK with it. Leaks caused by gutters eroding through the shingles are not covered by the shingle manufacturer’s warranty. It does not void the warranty for the whole roof, just for that specific condition.
Ask the Builder to show you where it says in the shingle or gutter manufacturer’s installation guide that it is OK to dump directly onto a shingle surface? Call the gutter manufacturer, and get their opinion. Ask for a detail on how to extend the downspout to the lower gutter… call the project designer and ask him if he wanted it that way. Lots of times the gutter installation is not detailed on the drawings and it is left up to the Builder, who leaves it up to the gutter guy who does it the way his Boss taught him to do it, who never read the code or an installation manual in his life…
I see this all the time (even by large national Builders on new construction). I call it out as wrong all the time, because it is not in accordance with the shingle or gutter manufacturer’s directions. They fix it all the time, because the Code supports the manufacturer’s opinion on how to do it right, and you can’t argue with the Code.
I highly recommend that Inspectors educate themselves on the product installation instructions for about everything we see in a house, because no one else reads those things… They are easy to pull up on-line as your write up your report. either that or stop saying you inspected it. If you don’t know exactly how a product is supposed to be installed, how can you say it is OK or not.
We can’t know everything, but we need to know a little more…
Good luck out there!