This section is from the book "A Treatise On Architecture And Building Construction Vol3: Stair Building, Ornamental Ironwork, Roofing, Sheet-Metal Work, Electric-Light Wiring And Bellwork", by The Colliery Engineer Co.. Also available from Amazon: A Treatise On Architecture And Building Construction.
It is very desirable to give a stairway a pleasing appearance at its start; with that end in view, the stairway is often widened adjacent to the newel by curving out the front stringer 6 inches or more, and increasing the width of several of the treads by gracefully curving the riser. In Fig. 34 is shown a plan of the first three steps of a stairway treated as suggested. On this plan the elevations of 3 of the risers and treads are projected in order to show the connection of the rail with the newel. Draw the bottom line of the rail through the points where the centers of the short balusters would occur, as at d d'; set off from dd' the thickness of the rail, 2 inches, and draw the center line of the rail e f. The tangents c b and c a on the plan are equal in length, and b is the point where the rail joins the newel. Make cg equal in length to cb; draw g f, c o, and a c, parallel to the riser lines; through o, draw h j at right angles to c o. If the rail is brought to a level on the line o j, its height will be 9 inches from the bottom step i to the center of the rail at j. In this elevation the rail has been drawn below its real position a distance equal to the height of a short baluster, or 2 feet 2 inches. This distance, added to 9 inches, gives 2 feet 11 inches as the height of the newel, from the first step i to the center of the rail at j. If the rail is continued straight to f its height will be only 2 feet 5 1/2 inches. If the newel is designed to meet the requirements of a plan-of this character, it is important to determine the exact height where the eased rail will connect, and the foregoing description will enable the student to do so.
In Fig. 35 is shown a stairway starting at the newel with a curved stringer and swelled steps; the newel in this arrangement is to stand on the first step, the riser extending around to the stringer which will receive it. Thus the newel does not project beyond the line of the first step, and, where the space is limited, this method will help to overcome the difficulty. The height of the newel in this case may be determined by the method explained for Fig. 34.
In Fig. 36 is shown a plan wherein the stringer is curved as in the previous examples, but, with the exception of the starting one, the risers are made straight.