The sheet acts as a backup at a vulnerable junction.
How to seal a flat roof against a wall.
The roof framing itself in this.
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.
Follow the photo for illustrated instructions.
When the roof of an addition garage porch or patio meets a brick wall the intersection creates a number of concerns.
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.
These kinds of houses often have a roof that butts against a wall.
Housewrap creates the foundation.
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.
Metal roof flashing can be use to seal gaps between roof walls.
Install base flashing under shingles or over metal roofing material.
Metal roof flashing is a galvanized sheet metal bent at right angles with about eight to 12 inches on each side of the angle.
How to frame a roof against a brick wall.
If the roof runs flat up against the brick wall you must install the roof side of the flashing either under the last layer of shingles or over the roof material if it is metal.
Proper roof wall abutment flashing examples.