The roof is an important part of a building or a house. It protects the housing from heat, rain, and contributes to the aesthetic appearance of the structure. What is roof scissors"

It is a structure that will hold the wooden crating. They correspond to the lattice girders structural system. They carried isostatic structures with bars located in one plane and connected to each other at their ends by joints called nodes, interconnected in the form of triangles constituting a stiff chain supported at the ends.  
There are more types defined by the architectural needs of the design and dimensions of the required structure, where we can have the following schemes. About the elements and other questions based on this, in the link bellow.

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