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Introduction On entering a building, almost the first thing that meets the eye is the staircase and unconsciously it is made to serve as an indicator of the quality of the architecture. If the design is poor or the construction faulty, this flaw immediately gives the visitor a bad impression of the whole building. Furthermore, stairbuilding is a rather difficult subject and the principles involved are very little understood, which is evidenced by the fact that the layouts as furnished by architects in their plans are often improperly done. Probably more mistakes occur in connection with the stairway of a building than with any other construction feature. It is with the idea, therefore, of giving a complete though simple presentation of the construction methods as applied to standard design of staircases, that this book has been prepared. The article discusses straight and winding stairs, stairs with well hole, layouts for curved turns, the proper proportions of rise and width of tread, the design of hand railings and many other problems, the solution of which will be found very useful. Coupled with this article is a most instructive section on the Steel Square, containing many applications of this useful instrument to roof and other types of construction. Stairbuilding - Introductory In the following instructions in the art of Stairbuilding, it is the intention to adhere closely to the practical phases of the subject, and to present only such matter as will directly aid the student in acquiring a practical mastery of the art. Stair-building, though one of the most important subjects connected with the art of building, is probably the subject least understood by designers and by workmen generally. In but few of the plans that leave the offices of Architects, are the stairs properly laid down; and many of the books that have been sent out for the purpose of giving instruction in the art of building, have this common defect that the body of the stairs is laid down imperfectly, and therefore presents great difficulties in the construction of the rail. The stairs are an important feature of a building. On entering a house they are usually the first object to meet the eye and claim the attention. If one sees an ugly staircase, it will, in a measure, condemn the whole house, for the first impression produced will seldom be totally eradicated by commendable features that may be noted elsewhere. It is extremely important, therefore, that both designer and workman shall see that staircases are properly laid out. Stairways should be commodious to ascend - inviting people as it were, to go up. When winders are used, they should extend past the spring line of the cylinder, so as to give proper width at the narrow end and bring the rail there as nearly as possible to the same pitch or slant as the rail over the square steps. When the hall is of sufficient width, the stairway should not be less than four feet wide, so that two people can conveniently pass each other thereon. The height of riser and width of tread are governed by the staircase, which is the space allowed for the stairway; but, as a general rule, the tread should not be less than nine inches wide, and the riser should not be over eight inches high. The Steel Square - Introductory The Standard Steel
Square has a blade 24 inches long and 2 inches wide, and a
tongue from 14 to 18 inches long and 1 inches wide. The blade is
at right angles to the tongue. The face of the square is shown in Fig. 1. It is always stamped with the manufacturer's name and number. The reverse is the back (see Fig. 2). The longer arm is the blade; the shorter arm, the tongue. In the center of the tongue, on the face side, will be found two parallel lines divided into spaces (see Fig. 1); this is the octagon scale. The spaces will be found numbered 10, 20, 30, 40, 50, 60, and 70> when the tongue is 18 inches long. To draw an octagon of 8 inches square, draw an 8 inch square and then draw a perpendicular and a horizontal line through its center. To find the length of the octagon side, place one point of a compass on any of the main divisions of the scale, and the other point of the compass on the eighth subdivision; then step this length off on each side of the center lines on the side of the square, which will give the points from which to draw the octagon lines. The diameter of the octagon must equal in inches the number of spaces taken from the square. On the opposite side of the tongue, in the center, will be found
the brace rule (see Fig. 3). The fractions denote the rise and
run of the brace, and the decimals the length. For example, a
brace of 36 inches run and 36 inches rise, has a length of 50.91
inches; a brace of 42 inches run and 42 inches rise, has a
length of 59.40 inches; etc.
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