Sloping Flat Roof Steel Truss Design

The steel roof truss is one of structural engineering s most important and iconic elements.

Sloping flat roof steel truss design. These steel joints are needed to support the overall truss. Flat the most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7 of the span in inches. If you want to build a flat roof then you will need to build a flat roof truss. A flat roof truss is also known simply as a flat truss and is not completely flat but rather slightly sloped in order to allow water to run off of the roof.

Sloping flat trusses are used almost like a joist in settings where the interior ceiling pitch is desired to be the same as the roof pitch. Use prefabricated mono trusses for the easiest and best framing on a single slope roof. They are used in construction of roofs of fairly large objects such as shopping malls logistical parks and warehouses. The live load shall be taken as follows.

These are designed to span the space between two load bearing walls and take the weight from the roof onto these walls. Most economical when the difference in slope between the top and bottom chords is at least 3 12 or the bottom chord pitch is no more than half the top chord pitch. Drains on flat roofs should be located at the low points. Flat roof truss design is used in intermediate flat structures because its spans are not of a much higher range.

I for sloping or flat roof with slopes up to and including 10 degrees. Live loads on roof trusses. A when access is provided 1500 n m 2 b when access is not provided 750 n m 2 except for maintenance ii sloping roof with slope greater than 10 degrees. Select an angle of slope away from a house into an area with good drainage and complementary to an existing house or other building.

Made of individual members with equal counteracting tensile and compressive forces its purpose is designed to behave as a single object which carries supports a load over a span. The same thing is true for the bridge of the truss. It s often used for sheds garages or extension of an existing roof. Measure the outline of the structure to be roofed with a tape measure or get dimensions from a house plan.

The more complex the truss framework is the greater quantity of these joints will be required. These are at the center of the span if the truss is built flat. Sloping flat trusses are typically supported by a ridge beam or girder truss at the roof peak and have sloping flat trusses on both sides to create wide open span spaces in public venues like riding arenas and churches. These structures generally have a flat roof structure because they are already at a high height.

Flat roofs with no slope for drainage are not recommended unless provision is made in the design for possible accumulation of water due to a stopped drain or natural deflection.