Roof Valley Against Wall

The exterior of a house presents plenty of opportunity for leaks.

Roof valley against wall.

A key part of my approach is using a special piece of flashing at this. Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Remove any debris from the valley by hand or with a utility brush. A common problem area is the point where a gutter dies into an adjoining wall as the photo below illustrates.

Here is an attempt though maybe not a very good one to make the roof flashing serve also as a through the wall flashing with a tile roof. In comparison to a closed valley an open valley adds another layer of lining into the valley. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles. The flat roofing material must go up the wall a minimum of 12 or up the wall and over the top of the wall if the wall is less than 12 high.

Unless you re careful step flashing can allow water from the roof to slip behind the gutter and get behind the siding and even the housewrap. Position an extension ladder against the lower edge of the roof near the valley that is repaired. Drip edge metal valley flashing dormer chimney and kickout flashing are types of roof flashing that shed water away from the connections between roofs walls chimneys and other building assemblies. Below are two photographs of roof wall step flashing completed and effective of a slate roof against a brick wall below left and in process with step flashing against a dormer sidewall before the dormer siding has been put in place below right.

Stop nailing 6 inches from the center. After the self adhering underlayment is installed across the valley a pre bent metal valley lining is installed. The asphalt shingles serve both as the valley lining and as the wear surface to protect against water. Proper roof wall abutment flashing examples.