Flat Roof Drain Through A Parapet

6 24 2014 david howard aia said.

Flat roof drain through a parapet.

Unlike most industry standard roof canales made of wood and sheet metal which deteriorate rapidly in a few short years our fiberspan concrete canales roof scuppers endure the most extreme of weather conditions for many years. It is generally used in channels scuppers or parapets. Usually you are not seeing a flat roof but a parapet or wall that contains the flat roof. A small diameter drain that mounts to a roof deck.

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. As a result the flat roof is usually angled on all sides towards the middle. It is generally used in channels scuppers or parapets. A parapet is a low wall projecting from the edge of a roof platform or terrace.

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. To use scuppers as a flat roof drainage system the roof must have a parapet or perimeter wall surrounding it. Drain spouts that protrude through the roof parapets are called canales. Canales are commonly made of wood reinforced with a metal lining.

To design a sloped or flat roof drainage system we need to know the anticipated maximum rainfall rate and the flat or projected roof area. 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. Typical methods include banding pitch pockets and cover flashings. These are fitted at either end of a parapet wall meaning the flat is typically angled in two directions from the middle.

An approved sealant is then applied to the top of the membrane upstand before it is tied off with a jubilee clip. Scuppers install into perimeter curbs and parapet walls on your roof and. Basic function on flat roofs and in parapet walls scuppers function essentially as a continuation of the roof membrane. It must be adjusted so that the roof slopes gently towards the scuppers to drain away from the structure.

What is the general area of a flat 1 4 1 0 slope single ply roof for each roof drain ratio for the number of roof drains roof area. A cover placed on top of a drain to control liquid inflow outflow and to keep large debris from clogging the drain opening. Banding is typically used to seal soil vent pipes on single ply roofs such as fdt rhepanol pib and involves wrapping an unreinforced membrane around the pipe to a minimum height of 150mm.