PLATE 2.
PLATE II.
CLOSE NEWELLED OR DOG-LEGGED STAIRS, THE SETTING OUT OF RODS, ETC.
Fig. 1 shows the plan of a dog-legged stair. The first thing to be done is to take off the sizes on a rod. First take the rod, marked Fig. 3. Cut this rod in between the brick walls, taking care to try it between the walls where the two flights come together at risers 12 and 13. Set off on each end of this rod the thickness of plaster; now set off the face of wall strings so that they will be flush with the face of the skirting. Then set back from face of the string half an inch, the depth of the housing, this will be the end of the treads and risers. Next set off the centre of the rod, draw the newel and string on the rod, half their thicknesses on each side of the centre line. Then set back towards the centre from each face of the centre string, half an inch, the depth of the housing. This gives the length of the treads and risers; and if ordinary care is taken in setting out this rod, and working to it, no mistake can be made.
The height rod is seen at Fig. 4. Set off on this rod the height from the top of the bottom floor to the top of the top floor. Now divide this height into as many parts as there are to be risers, and the distance from one division to another represents the height from the top of one tread to the top of the next. The number of risers and the height of them must be regulated by circumstances. A few hints only can be thrown out here. The rise should not be less than 6 inches or more than 7¼ inches, while the going and the rise added together should not be less than 16½ inches or more than 18 inches. Thus, it will be seen, the going should be regulated by the rise. For instance, say the rise is 7¼ inches, then the going should not exceed 10¾ inches; this would make the going and rise added together 18 inches. Now, the stairs would be easier if the going was only 9¾, as this would make the two 17 inches, which is a better average than 18 inches. These remarks are not laid down as a fixed and unaltered rule, but are intended as a guide in the setting out of stairs of any description. Mark off on the height rod the floors, joist and ceiling of both landings, as shown at Fig. 4. In putting in the landing, use the height rod to get the height of the joist, but care must be taken to take the height from the proper floor level, in case the floor is not down.
Fig. 5 shows the going rod. Put one end of this rod against the back wall, and mark on to it all doorways, trimmer joists, &c. The width of landing and the going must be regulated by circumstances, but the risers, newels and all joists must be marked on to the rod as shown. In putting in these trimmers it is always as well to square them, that is, put them in square to the side walls, then should the back wall be out of square the difference will be in the landing.
Fig. 6 shows the pitch board. These are best made of zinc. Make the rise equal the height of one rise on the height rod, and the going equal the going of one step on the going rod.
Fig. 7 shows the construction of one step. A plan and elevation of the stairs should always be made to a scale of, say, ¾ of an inch to the foot, or, if possible, to 1½ inch to the foot, and all openings, headroom, &c., should be shown. The line H H, Fig. 2, is drawn parallel to the line of nosings on the bottom flight, and at a height above them of 7 feet. Then the bottom edge of the top landing must be kept above this line to give sufficient headroom. The setting out of the strings and glueing up of the steps, &c., will be seen on [Plate III].
PLATE 3.