# As This Formed A Ladder

We all know what are stairs. (Source: David Zwirner). The stairs are artifacts that allow us to settle spaces at different heights and accompany us since ancient times (estimated that they began to appear with some regularity around the 6000 before Christ). We also know that there is a great variety of kinds of stairs: straight staircases, spiral staircases, retractable stairs, stairs bunk but few of us know how the stairs and what parts are composed. Here I will briefly describe their different parts. The first thing that catches our attention are steps or rungs.

A step consists of two elements: a horizontal part that is called a footprint or pedada and that is where the foot is the support, and a vertical part which is often called riser or lump and that is the height of the tread, i.e., the space which mediates between two footprints or a footprint and floor. The relationship between these two parties must be regular and consistent so that the ladder is passable. The angle or slope resulting from this relationship between the two Parties shall determine the degree of comfort and accessibility of the staircase. The succession of steps of a ladder is called stretch and usually limited by two breaks. The standard indicates that each section should consist of twenty-one steps. The rest of the stairs must have a minimum width equal to the width that holds the section which precedes or continues. It also has to offer the stair user comfortable and easy interruption of at least eighty-five centimeters in length.

There are two kinds of rest: intermediate which sits between two flights of stair and the arrival that ends the tour. Stairs, according to their functionality, can be closed or open. The closed staircases are wrapped by the call box, which is a structure that contains the different stretches and whose function is to offer enough privacy and security in the first place. The box shape can vary depending on circulation and the height that has to save. The lateral limits of the stairs are called Stringer (also usually receive the name of) lemon) and can consist of a line, when only limits are represented in plant, or in a structural element when those limits are materialized. Track line: indicates the route that a person makes to the upload. In general, that line goes in the center when the same width is less than 1,10 m, otherwise the measure is 50 to 55 cm inner lemon (since people grab the railing). Both the footprint and the riser must be constant throughout their journey. The eye of the staircase is hollow interior space that lies between two sections. According to the design of the staircase, this eye may or may not exist. Straight stairs, for example, do not have this hollow space. Next to the eye it is often found inside lemon or collar, or the inside edge which limits the stretch of the stairway. There is a minimum width of 12 inches that must be respected in the layout of the track and indoor lemon. All these parts are articulated to contribute to the structural functioning of a ladder. To them must add guardrails or railings, which are braces that stair user serves to raise or lower. The average height is usually be around eighty-five centimeters. Baluster, finally, is the set of handrails and handrail of a stairway. Original author and source of the article