The perfect finish of the good building construction is a great roofing system. It should be nice looking, quality build and perfectly strong element of the house that would keep the building safe and dry. Open cornice, box cornice and close cornice are the three types of cornices which are mostly used in residential construction.  
Roofing material which is seen of the outside of the construction is supported by roof sheathing which usually refers to plywood or other sanctioned panel products. Read further from the link bellow. 
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