Dundalk · Blackrock · Ardee · Co. Louth
Flat roof observation notes
On most Dundalk houses the flat roof is the later bit: the kitchen extension, the garage, the box dormer. It often leaks for different reasons than the slate at the front.
From an upstairs window, about twelve hours after rain: - Is water still lying on it? A flat roof is built with a slight fall and should drain. Photograph any puddle with the date. - Is there a split or a lifted edge where the flat roof meets the house wall? - Is the stain inside a ring around a rooflight? Rooflights usually leak at the frame, not the glass. - Is there green growth on one side? That marks where water sits. Inside, note whether the drip is at the wall, around the rooflight or in the middle of the ceiling. A drip in the middle of the room under a puddle points at the fall or a puncture. A drip at the edge points at the joint with the wall. Listen in heavy rain. Some extensions have an internal downpipe hidden in a cupboard. If it gurgles, the outlet may be the problem, not the felt. Write down roughly when the extension was built and whether it has been recovered before, and how often, if you know. Mineral felt on an old garage and single-ply on a newer dormer are different jobs. Three recovers on the same boards usually means the deck needs looking at as well. Do not walk on felt to check. Old boards can give without warning.
The roofer should say whether it is the fall, the wall joint, a rooflight or a puncture before suggesting a full recover.
Photos of any ponding from a window after rain, the room underneath, and the age of the extension if you know it.
On Dundalk houses the flat roof is usually a later add-on, so the slate you can see from the street may not be the problem.