Risers And Treads. Upon the common stair, such as attic and porch, etc., treads and risers are placed as in Fig. 120, being nailed to place, risers first and then treads.
On porch steps and open stringers, the treads should overhang at their ends an amount equal to that given the front. The cove, if one be used, should be carried around and "returned" under the end of the tread.
On enclosed or semi-enclosed stringers, a combination of stringer and wall board is commonly used. Fig. 125 illustrates a type of construction often used upon attic stairs. In this the side stringers are framed of 1" stock and then nailed to the wall board of similar thickness. Such construction is not suited for first floor stair work where the effects of shrinkage would show to greater disadvantage.
Fig. 126 illustrates the manner of framing a modern stair suitable for a first floor where the best type of construction is demanded. As a rule, such stair work will be done at a mill and the stair brought to the building knock-down. The carpenter will have framed the rough stringers which are to support the ceiling below the stair, and placed them so that they may be used as a temporary stair for the workmen. If the stairway is an open one or semiopen, the plastering under these stringers will have been placed, the stair being put together on the floor and then raised to its place. If the well-hole is such that the stair must be assembled while the strings or wall boards are in place, the lath and plaster must be left off the rough stringers until after the stair has been assembled and the wedges glued and driven in place as shown in the illustration. Rough stringers must be placed far enough from the sides of the well-hole so that the wall board may settle in place and that the wedges may be easily placed, usually about 4" or 5" from the wall will be sufficient.
Fig. 125. Stringer for Attic Stair.
Fig. 126. Main Stair Detail.