At the least, the two drainage
vents evident in the above picture should have been positioned at the lowest
point of the rainwater flow, not over 60cm up the slight gradient.
There should have
a slope on the floor/ground level so that the water ran twds the
a drainage gutter along the
perimeter of the glass ceiling (on the LHS of above pic)
probably about 5m in length
As a result rainwater remains until it evaporates, or leaks thru the 25 years old waterproofing,
which was discreetly covered by stone pebbles, likely to conceal the drainage flaw
during the six years builders warranty period.