It serves as an extension of the wall by which the roof is supported.
Flat roof parapet repair.
The slope should be a minimum of 1 in 80 but in practice a minimum slope of 1 to 40 should be used to allow for deflection of the roof and for normal building tolerances.
Of course flat roofs are not flat but have a very slight roof pitch of between 1 4 to 1 2 per foot.
Many flat and low slope roofs are surrounded by parapet walls.
This gives the roofs of building a flat roof look.
This new torch on flat roof is leaking because the parapet walls and the coping stones are defective water damage to the ceiling below from the leaking ceil.
Just enough slope to drain water but also flat enough to be a problem if not constructed properly.
Parapet walls are a practical solution for providing a boundary between neighboring properties roofs.
As a roof ages the roofing seams begin to separate often beginning where the flat roof meets the parapet wall.
Parapet walls offer protection against fire because they impede the spread of fire by making a boundary on slanting roof.
Courtesy of max baker and the national research council of canada.
For clarity flat roofs actually have a slight slope to allow rain water to drain off the roof but they seem flat when compared with more traditional steeply sloped roofs.
If you didn t get it right you concentrated the stresses at roof edges and you could suck in a parapet or tear or rip a membrane at the parapet photographs 3 and 4.