Table Of Vertical Dimensions Of Stair Posts

Concerning the sizes of the posts in the above table, it will be well to remember that a 6" X 6" post will be about 5 3/4" x 5 3/4", and a 4" X 4" post will be about 3 3/4" X 3 3/4" when they have been planed on all four sides, though the usual way of speaking of them is upon the basis of their sawed dimensions.

If it is necessary that the base, or bottom square, of the newel post should receive more than one riser, or that the bottom square of the winder receive more than four risers, and the top end of the lower stringer or carriage, the aggregate height of the desired risers may be added to the length of the bottom square. If the angle included in the winder contains three risers, instead of four, the top of the bottom square should be lengthened the height of one riser, and the turning shortened an equal distance, to allow a landing for the top of the lower rail against the bottom square of the post.

The distance a of the newel post (Fig. 69) may be about the same as distance b of the platform post, though the newel post is sometimes set so that the bottom riser will come 1 1/4" from the front of the post, instead of 3 1/2" as indicated. This requires that there should be one less baluster upon the lower tread, and that the shaft of the post should be enough longer to allow the rail to land in the middle of the vertical height of the square. The dimensions indicated upon the table will generally be satisfactory, as the bottom square is often made somewhat longer than necessary, in anticipation of the necessity of adjustment and of scribing it to the floor. The height of the rail may be varied a little to allow it to come as near the middle of the square as possible.

The bottom square of a winding post, unless laid out for a certain place, should be about three inches longer than actually required, as any variation in the rise should be corrected at this place if possible, rather than by raising or lowering the rails sufficiently to make them perceptibly out of pitch. The rosettes (/) should be turned separately, and nailed on after the bottom square has been cut to its exact length. This is the practice of many stair-builders, but others prefer to have the rosette turned on the post, and allow the bottom square to extend as it will below the ceiling or stair stringer.

The bottom squares of the landing, gallery, and starting posts are usually so cut that they apparently extend through the floor. They are notched over the thickness of the floor, which includes the ceiling, floor joists, and flooring, to rest against the side of the floor joist or header, the bottom end of the post showing its full size, ornamented with a rosette, as at d of the starting post. It is the custom of some stair builders to face the thickness of the gallery landing or floor its entire length, and notch the bottom square of the posts as above described; however, the post rests against the facing instead of the facing being cut against the post; in this case, the post projects 1 1/4" to receive the nosing and scotia of the finish.

Upon common work, the riser between the last tread and the floor level, and the facing of the thickness of the floor, are often cut in square between the posts with a simple butt joint, but in the better class of buildings they are mortised into the posts, the same as in the winder and platform posts. It is plain that the former method will be affected by any settling of the building, while by the latter, the joints will not open. The bottom of a post which extends down upon a plastered or paneled wall, or in a corner, should be finished as shown by the bottom square of the gallery post.

A turned post should be laid out accurately, or there may be trouble in making the rails, stringers, and risers join it properly. Upon the best class of work, turned posts are rarely used, some simply designed square post being in much better taste, in which case the connections may be made more easily, the post being cut to length at the bottom end, when its length can be measured exactly at the building.

51. Treads and risers. - Different methods of putting the treads and risers together are illustrated in Fig. 70.

The method shown at a is in common use upon the better class of work, as the tongue and. groove joint between the tread and riser at h prevents dirt from sifting through, and minimizes the effect of the shrinking of the tread and riser.

Some stair builders tongue and groove the riser into the tread above it, as shown at b, but the front edge of the tread is thereby weakened, so that when it is somewhat worn from rough usage, it will break off more easily than if the groove were not there. The cheapest form of construction is shown at c, all of the joints being square, with no grooves. This form is suitable for the cheapest class of work only.

The forms of moldings or nosings in common use for finishing the edges of treads are shown at d, Fig. 70, and the scotia at e.

A method of embellishing the risers of a flight of stairs which is capable of either simple or elaborate application-is illustrated in Fig. 71. This method requires that a distance equal to the thickness of the scroll should be cut off from the shoulder, or from the plumb cut of the top of the stringer, and that the mortise in the post should be set back an equal distance, as it is obvious that the face of the scroll should be considered the face of the stringer, and the mortises in the posts made accordingly. This method differs from the plain miter only in the addition of the scroll, in cutting the shoulder of the stringer to allow the risers to come where they would if a plain stringer were used, and in fitting a piece the same thickness as the scroll to prevent a hole between the face of the stringer and the back of the nosing (b). The risers and treads should of course extend to the outside of the scroll. The nosing, or the finish of the ends of the tread (b), is a separate piece, mitered into the front edge of the tread at c; the scotia (d) is mitered around the scroll at e. The back end of the nosing (b) should be returned upon itself in its proper relation with the scotia (d) and the bottom of the scroll of the riser above, which should be designed with this in view.