Housed strings are those which carry the treads and risers without their ends being seen. In an open stair, the wall string only is housed, the other ends of the treads and risers resting on a cut string, and the nosings and mouldings being returned as fore described.
The manner of housing is shown in Fig. 19, in which the treads T T and the risers R R are shown in position, secured in place respectively by means of wedges X X and F F, which should be well covered with good glue before insertion in the groove. The housings are generally made from ; to s inch deep, space for the wedge being cut to suit.
In some closed stairs in which there is a housed string between the newels, the string is double-tenoned into the shanks of both newels, as shown in Fig. 20. The string in this example is made 12i inches wide, which is a very good width for a string of this kind; but the thickness should never be less than 1-1 inches. The upper newel is made about 5 feet 4 inches long from drop to top of cap. These strings are generally capped with a subrail of some kind, on which the baluster, if any, is cut-mitered in. Generally a groove, the width of the square of the balusters, is worked on the top of the subrail, and the balusters are worked out to fit into this groove; then pieces of this material, made the width of the groove and a little thicker than the groove is deep, are cut so as to fit in snugly between the ends of the balusters resting in the groove. This makes a solid job; and the pieces between the balusters may be made of any shape on top, either beveled, rounded, or moulded, in which case much is added to the appearance of the stairs.
Fig. 21 exhibits the method of attaching the rail and string to the bottom newel. The dotted lines indicate the form of the tenons cut to fit the mortises made in the newel to receive them.
Fig. 22 shows how the string fits against the newel at the top; also the trimmer E, to which the newel post is fastened. The string in this case is tenoned into the upper newel post the same way as into the lower one.
The open string shown in Fig. 23 is a portion of a finished nosings and cove returned and finishing against the face of the string. Along the lower edge of the string is shown a bead or moulding, where the plaster is finished.
A portion of a stair of the better class is shown in Fig. 24. This is an open, bracketed string, with returned nosings and coves and scroll brackets. These brackets are made about
inch thick, and may be in any desirable pat tern. The end next the riser should be mitered to suit; this will require the riser to be inch longer than the face of the string. The upper part of the bracket should run under the cove moulding; and the tread should project over the string the full 5 inch, so as to cover the bracket and make the face even for the nosing and the cove moulding to fit snugly against i ie end of the tread and the face of the bracket. Great care must be taken about this point, or endless trouble will follow. In a bracketed stair of this kind, care must be taken in ing the newel posts, and provision must be made for the extra t inch due to the et. The newel post must be set out from the string inch, and it will then align with the baluster.
We have now de scribed several methods of dealing with strings; but there are still a few other points connected with these members, both housed and open, that it will be necessary to explain, before the young work man can proceed to build a fair flight of stairs. The connection of the wall string to the lower and upper floors, and the manner of affixing the outer or cut string to the upper joist and to the newel, are matters that must not be overlooked. It is the intention to show how these things are accomplished, and how the stairs are made strong by the addition of rough strings or bearing carriages.
Fig. 25 gives a side view of part of a stair of the better class, with one open, cut and mitered string. In Fig. 26, a plan of this same stair way, IV S shows the wall string; R S, the rough string, placed there to give the structure strength; and 0 S, the outer or cut and mitered string.
At A A the ends of the risers are shown, and it will be noticed that they are mitered against a vertical or riser line of the string, thus preventing the end of the riser from being seen. The other end of the riser is in the housing in the wall string. The outer end of the tread is also mitered at the nosing, and a piece of material made or worked like the nosing is mitered against or returned at the end of the tread. The end of this returned piece is again returned on itself back to the string, as shown at N in Fig. 25. The moulding, which is L-inch cove in this ease, is also returned on itself back to the string.