Water – Roofing solution for “dead valley,” where one plane goes into side wall



I am reworking my roof on the front of my house. The previous roof had been leaking down the corner of the house where the garage and porch roofs come together. The previous roof had a sort of false roof added to create a plane moving away from the sidewall, although this seemed to move the problem down.

1. Roof Valley Before

Roof Valley Before

2. Roof Valley Before Showing Corner Damage

Roof Valley Before - Corner Damage


I have seen some references to low slope roofing membranes like these: http://www.gaf.com/Roofing/Residential/Products/Low_Slope_Membrane/Liberty, is this the way to go?

I just want to make sure water flows out of this area and over the corner without leaking as shown in the pictures.

3. Roof Valley Now
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Best Answer

Solution I ended up with:

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I extended the shingles well over the edge (not shown) and also added some kick out flashing (not shown) to further divert water away from the side wall and to the roof plane below. enter image description here