Tracing a balcony leak to one detail
How water got past a balcony membrane, and how the cause was found.
In short: Balcony leaks are often blamed on the membrane. In this investigation the cause was the flashing at the wall.
The symptom
Water was appearing below a tiled balcony after rain.
What was tested
With pavers lifted, the membrane was flood tested and appeared to hold.
The cause
Rain running down the wall above was getting behind a face-fixed perimeter flashing sealed only with silicone.
Why the detail matters
Water follows the easiest path. One poorly detailed junction can defeat a sound membrane.
Written by our local inspection team from work carried out in Sunbury. Licensed building practitioners, Building & Plumbing Commission registration CDB-U 53425.
