Building defects database - Damp penetration: leaking downpipe

Record details

(a) A downpipe ran against the exterior of the wall shown in image (b) below. A sharp bend at the base of a downpipe, such as that shown, will always be prone to blockage, causing water to back up in the pipe above. Downpipe joints are usually only dry interlocking sections, so once the accumulation has backed up far enough water will leak from the joint above the blockage, spilling down the adjacent wall, causing the internal staining.

(b) Dampness in the corner and by the window on this stairwell wall seemed to be penetrating from outside, see image (a) above.