Spiral staircase is a construction complex project that requires a serious approach. Such work is usually trusted to professionals, but if you do decide on building a spiral staircase by your own, so you need to start with the design and calculations. Determine the type of structure first, which will need a subsequently calculations. The design of the side supports is called “well” in the walls of which are built in stages, or spiral string. The role of the casing support is very important and you can use a steel pipe with a diameter 6-8 cm with a wall thickness of at least 5 mm.  Frame consoles can be welded steel bracket. The material for the steps consoles is good to be wooden array. A spiral staircase is a failure in terms of the right circle whose diameter is equal to the diameter of the opening. The radius of the circle (R) is called the radius of the opening or the outer radius of the console. Opening the inner radius (R1) can be calculated as the radius of the pipe-support + thickness of its wall. More, from the images in the gallery schemes.

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