Structural Design Steel Roof Truss

You will also incur additional costs because it is much harder to deck and shingle a roof that is 12 12 pitch versus a 4 12 roof.

Structural design steel roof truss.

A truss is essentially a triangulated system of straight interconnected structural elements. Structural model of truss truss girder self wt 4 05 k 4 05 k 80 ft x 25 ft 2 03 psf 18 03 psf bar joist wt 9 plf pd int dead load at an interior panel point 18 025 psf x 25 ft x10 ft 4 51 k due roof ceiling wt truss girder 9 plf x 25 ft 0 225 k due purlin wt 4 73 k pd. This is the distance between trusses. Long span curved roof trusses.

Design of roof purlins 6 for efficient structural performance it is recommended that the truss span to depth ratio be kept between 10 to 15. It is desired to specify the appropriate angle sections that will safely carry the anticipated loading using eurocode design code specified steel grade s 275. The standard roof truss spacing is 2. The skeletal structure of a roof system 18 0m long and 7 2m wide is as shown in figure below.

Knowing the expected live and dead loads the bearing points overhangs and other structural factors spans over 300 can be engineered with these steel trusses. 1 4 2 general geometry in order to get a good structural performance the ratio of span to truss depth should be chosen in the range 10 to 15. Steel roof truss design calculator hood roof bonnet roofing systems are basically a mansard roof backwards. An advantage of the truss design for roofs is that ducts and pipes that are required for operation of the buildings services can be installed through the truss web.

There are parallel and triangular and trapezoidal trusses. The main reasons for using trusses are. Arches are particularly useful with this application creating large enclosed or semi enclosed structures such as aggregate storage facilities barns manufacturing enclosures workshops etc. Different steel roof truss designs are prepared depending upon the shape of the structure.

Parallel trusses are used for deep roofs whereas triangular are usually employed in the trusses with steep pitches. Likewise referred to as kicked eaves a hood roof has 4 sides with a high top incline as well as a much more mild reduced incline offering cover around the sides of your home for a veranda. The steeper the roof the more expensive the trusses get because the longer the boards get and the more roof area increases.