Missing Kick-Out at a Roof-Wall Intersection
A one-story stucco addition has a shed roof that dies into the stucco wall. Step flashing is visible along the roof slope, but at the low end, where the roof meets a vertical wall corner, there is no kick-out flashing. The stucco extends down to within about 1 inch of the shingles and is sealed with a bead of sealant at the roof-to-wall joint. Inside, a water stain covers about 2 square feet of ceiling at the same corner. Exterior moisture readings are 26 to 30 percent in the stucco 12 inches above the roof line near the corner, compared with 12 to 14 percent 6 feet away. The attic shows dark staining on the roof sheathing at the wall corner. A downspout from an upper roof discharges onto the lower roof about 4 feet from the corner.
1. Identify the defect and trace the likely water path.
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The missing kick-out flashing is the primary defect. Step flashing is installed in individual pieces along the roof slope, but at the low end of a roof-to-wall intersection, water running down the step flashing must be thrown out onto the roof. Without a kick-out, that water can run off the end of the step flashing and into the wall at the corner. The sealant bead at the stucco-to-roof joint is not a substitute; it is a maintenance seal, and water can pass behind it. The downspout discharging onto the lower roof about 4 feet away adds flow and splash to the same corner. The interior ceiling stain and attic sheathing stain line up with that path, and the exterior moisture readings are concentrated near the corner. The likely path is roof water to the step flashing end, behind the stucco, into the wall assembly, then to the ceiling and attic sheathing.
2. Why is step flashing plus sealant insufficient at this termination?
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Step flashing protects the roof-to-wall joint only for water that stays on the roof plane. At the bottom end, the step flashing has an open edge; without a kick-out, water can follow the flashing back into the wall. Sealant at the stucco face may look continuous, but it bonds to a surface that moves and weathers, and it cannot redirect the volume of water that a roof plane delivers. Stucco and building paper are not a waterproof barrier at that joint. A proper detail combines step flashing, a kick-out that turns water onto the roof, and a counterflashing or sealant detail that keeps water on the exterior. The stucco should also terminate above the roof with a gap or proper flashing, not within 1 inch and sealed.
3. What repair sequence and verification would you recommend, and how would you report it?
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I would recommend removing the lower stucco at the corner to expose the step flashing and wall sheathing, installing a kick-out flashing that discharges onto the roof, and correcting the stucco termination so it does not rely on sealant. The wall's weather barrier should be lapped over the flashing, not behind it. The downspout should be redirected away from the corner. After the repair, a water test at the roof-wall joint would be appropriate, with interior verification. The report should describe the missing kick-out as a defect, explain the observed staining and moisture pattern, and recommend repair by a qualified roofer or stucco contractor. I would not state that the ceiling stain is definitely from this defect without an exploratory opening, but I would call it the most likely path.