Unapproved Valley?

Anyone looked into seeing if this technique for valley shingle is approved? I could not find approval. The bottom of the shingle is turned so it aligns with the centerline of the valley. Seems to me water could get underneath at the end seams.

Looks fine from here.

What don’t you like?


Agree, nothing wrong with it. Single cut valley/ or closed cut valley.

They didn’t cut it. They turned the bottom of the shingle to align with the centerline of the valley, then laid the course on top of that. So, you have butt joints going up the valley.

I’m not explaining this right. They laid the left side. Then they took shingles and created what looks like a cut by taking shingles and laying what should be the bottom edge along the valley so the bottom of the shingle goes up the valley. Then they ran the right side up to that. Its hard to see, I almost missed it and I was on the roof! It seems to me it could leak at the butt seams at the shingles laid going up the valley at an angle.

Like this?


It does look like the bottom layer on the right side is laid parallel with the valley…

Yes that is another method. See my post above yours.


As Mike says.

You need to check the manufacturer installation standards for the specific shingle in question. The technique is very common down here, because it saves cutting at the valley. This method should never be used with 3-tab shingles though.

It’s called a California cut valley. It’s not necessarily a defect, but it’s not listed in all manufacturers installation instructions as a recommended valley installation method.

Mike Larson, that is it! Problem is, you cannot see how far over they ran the left side. I wrote it up for further inspection, so let them figure it out.

You did a disservice to your client by calling for reinspection.

Seriously, why should anyone pay you to look at a roof if you’re going to automatically tell them to pay someone else to come behind you and do what they hired you to do?

That’s the second time this week someone said that. You can’t write something up so someone else can figure it out. That’s your job.

Juan, how can I make sure the left side, which seals the butts was done properly when I can’t see it. I would be doing a disservice by NOT calling it out. Let them decide if it’s something they want to look into deeper.

Juan, and you never recommend further investigation into structural issues you suspect but can’t see? You just spend a whole day figuring it out? Bust into walls?


  • you can’t see under the foundation: recommend further inspection
  • you can’t see behind the bricks: recommend further inspection
  • you can’t see the wiring in the walls: recommend further inspection
  • you can’t see the plumbing in the walls: recommend further inspection
  • you can’t see inside the evaporator coil: recommend further inspection
  • you can’t see the heat exchanger: recommend further inspection
  • you can’t see inside the water heater tank: recommend further inspection
  • you can’t see the irrigation pipes underground: recommend further inspection

Did we miss any trades that you can dump your work off to? This is a perfect example of a referral inspector who does little more than look for an excuse to tell the client to pay someone else to do what they were deceived into thinking the inspector was going to do for them.

Guess what: the person who your client hires to come behind you can’t see concealed details either. So exactly what benefit did you provide to anyone other than to fool yourself into thinking you were transferring liability back to the client? You wasted your client’s time and money twice: first when they hired you and second when they hired someone else to come inspect your non-defect. I hope you’re cheap at least.

Things that cannot be reasonbly observed because they are concealed should be disclaimed as not accessible.

How do you know the walls were framed properly with all of the drywall in the way?

You missed the point.

I remember when I first observed a California cut valley. It didn’t look right. But I went online and researched it. I read Kentons article, and probably asked the question on this board. In the end, I learned what it was and didn’t recommend further evaluation. It was fine as far as I could see.

We always find stuff we don’t recognize, but we can’t just recommend further evaluation every time and let everyone else figure it out. We need to Figure it out for ourselves and our clients.

I am a carpenter and our roofers install them that way, have never had any issues. I would have commented on the fact they have them tight into the valley, like Mikes pic shows they are off the center line 2 inches. I have seen I tight cut valley like that leak until it was cut back. Can you check from in the attic and see if there were any stains on the valley rafter.

“NRCA does not recommend a closed cut or California valley construction in climates that experience snow loads or heavy rainfall (in terms of frequency or intensity) or in locations that are exposed to accumulation of debris, such as leaves and other natural elements.”

Tom Bollnow - NRCA’s senior director of technical services.