Remodeling Tips and Reviews

Shingling a Valley with the California Valley method

Shingling a Valley with the California Valley method

Sep 17, 2012

There are several methods of shingling valleys with 30 year shingles, but the California look is, in my opinion the best looking and cleanest of them all. It also produces less waste and takes less time since there is minimal cutting involved.

The Bottom Row of Shingles

Essentially with the method you will start at the bottom of the valley at the roof edge and lay the shingles staggered around 4-6″ as you move up the valley. Make sure to keep the valley covered with 12″ minimum of shingle on each side. You do not want a butt seam in the valley. If necessary cut a previous shingle back to make this a clean system. If you are going to shingle towards a gable with straight cuts or a hip then starting in the valley and moving out is the best method.

California valley running out to a small gable end. Notice the stair stepping as the shingles straddle the valley.

When nailing, I like to put 2 nails on each side of the shingle, making sure they they are not within 6″ of the valley. Lastly I place a nail in the upper side corner of the shingle where it turns up the roof. This is done all the way to the top of the valley.


Top Row of shingles in the California Valley

The top row is where all the time saving comes into play. In other systems you will have to cut each single to sit in the valley and unless you are a pro and have a lot of experience the valley likely won’t look perfect. With this system, getting a clean look is a breeze.  The first thing you will need to do is put a mark 2″ from the center of the top of the valley on the unshingled side where the top layer of shingles will run in the other direction. Then place a a mark 2″ + an additional 1/8″ per foot of the valley length at the bottom of the valley. So a 10′ long valley would need roughly 3 1/4″ from center.

Looking closely you can see the bottom row of shingles on the upper side and the vertical shingles barely visible running up the valley with the top row moving off to the lower left.

Once the marks are made you will then snap a chalk line and starting from the bottom, place shingles longways up the valley with their edge facing the chalk line all the way up. This will create a clean line appearance in the valley for the top row of shingles and also help move water straight down the valley. You will nail this row of shingles like normal. The top row of shingles is then started at the bottom with the lower corner starting at the edge of the vertical shingle to create a clean appearance as you move up the valley. A 2″ line of roofers asphalt cement is then applied under the vertical row of shingles.

Graphic of the California roofing valley technique.