Parapet Roof Drainage Design

Manually adjust roof planes to have a negative pitch to create a parapet wall structure with a center drain.

Parapet roof drainage design.

Buildings that incorporate flat roofs with centralized roof drains and internal downspouts are another story. This type of pattern is particularly useful on buildings that are easily divided into rectangular areas. The drainage requirements for flat roofs on buildings present some special problems that we describe and illustrate here. From a roof edge.

However these days parapets add a lot more to a flat roof than just a cosmetic detail. Architectural home design software all content support videos chieftalk forum. However parapets block the drainage of rainwater from freely flowing over the roof edge. Requires a primary drainage system with.

From the edge of a valley. The premise of the pattern is that a drain is positioned in the center of the rectangular area and there is a four way positive slope into the drain. Install a drain at most 50 ft. Looking at a building from the ground a parapet may seem to simply be a design choice that adds little more than a characteristic look to a building.

Adding a parapet wall makes a flat roof far safer than leaving the roof s edge exposed. Limit the number of parapet walls. Keep the distance between drains to at most 200 ft. Parapet and valley gutters are treated differently because they have a higher risk of failure.

It s also sometimes used in tandem with scuppers. The most dependable type of roof drainage design is the inverted pyramid pattern. Provide adequate flashing for parapets openings walls joints skylights etc. On larger and more complex schemes specialist consultants may be employed to design the rainwater drainage system.

This would be in situations where a retaining wall or parapet prevents direct access to the roof s edge. This kind of drainage system is most common on small flat roofs where water volume and buildup isn t extreme. In many cases these buildings have parapet walls that surround the perimeter of the roof. Roofs of this design will have one or more roof drains or scuppers installed.

In these cases the. Typically surrounded with parapet walls to screen roof top equipment and to provide. Watch for clogs blockage at the roof drain or scupper. Install a drain at most 50 ft.

Back up secondary emergency drainage system in case the primary drain. At page top and at left our photos show a low slope roof surrounded by a parapet.