Roof Valley Against Wall

If you don t direct water from the roof into a gutter it can pour into the wall.

Roof valley against wall.

Proper roof wall abutment flashing examples. Avoiding problems begins at the beginning with a gap. Water collects in a valley to flow off the roof. The valley area of a roof the straight lines formed when two different planes of the roof meet is a critical area that handles a tremendous amount of water run off.

One layer each of felt underlayment mineral surfaced roll roofing and two layers of shingles. Stop nailing 6 inches from the center. Valleys are typically found where gable dormer roofs meet the main roof or when a house has angled wings or additions where two roof sections in different planes meet. Ideally i like to start by installing a 3 ft.

Essentially there are three main ways to shingle a roof valley. Metal roof flashing is a galvanized sheet metal bent at right angles with about eight to 12 inches on each side of the angle. Sheet of housewrap or even better a piece of self adhering roof underlayment to the wall before the first truss or roof rafter is placed against it. A roof valley is formed where two roof slopes meet.

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. 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. It is commonly used in two story and side split houses. Closed cut shingle valleys work fine with strip shingles and laminated asphalt shingles.

Lay one and two tab shingles as you near the valley so full size shingles will run across the valley. Roof one side of the valley running the shingles across it. These kinds of houses often have a roof that butts against a wall. The sheet acts as a backup at a vulnerable junction.

Ground zero for roof rot is often where roofs meet walls. 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. Housewrap creates the foundation. Snap a chalkline 2 to 3 inches past the valley center on the top layer of shingles.

Recommended procedures of basic valley flashing installation. Woven closed cut and open. Install an underlayment centered in the roof valley. Your choice of valley installation method is critical because when improperly installed valleys are risks for serious leaks.

A closed cut roof valley will have at least four layers of roof materials.