The roof is the upper component of the coating that protects the structure from atmospheric precipitation and various mechanical influences. This is a very important component of the structure, the resistance and safety of the entire extension depends on its reliable work, taking grinding and equipment in calculation. By the type of waterproofing layer, appearance and roof size, it is divided into five key types: roller, mastic, membrane, leaf and complete. A staircase is a practical and at the same time aesthetic component of the interior or facade of the house. By the type of stairs, there are varieties: a) forged; b) modular; c) attic; d) combined; e) ridge; e) console; e) spiral, g) marching. The roof is a necessary element so that each structure is of high quality and nothing superfluous could get into it, despite the street weather conditions, and chairs for bars and cafes, an important attribute that provides an opportunity for everyone to sit at a table of coffee or tea and Not only. A window is a hole in the wall of the room, usually located above the floor and is intended to guarantee a passage to the room and air, which is considered the sign of the sun and the eyes of the house. The types of windows include: motionless windows, rotary and rotary-pollinating, leaning, multi-willed, as well as windows that open in both directions.