Fig. 38. Threshold Detail
For the 3' x 7' door, Figs. [37] and [38], estimate the opening as follows: Height of door, 7'; allowance for rough floor, ¾"; finish floor, ¾"; threshold, ⅝" to ¾", head jamb and space for lugs of side jambs, 2" to 3"; total from joist, may be 7' 5".
For the width of opening estimate: Width of door, 3'; width of casings, at 4½" each, 9"; total spacing of studs center to center, 3' 9". Distance between studs will be 3' 7". This will leave space enough to put the doubling studs on each side between header and floor. Since locations of openings in the main frame, both window and door, are dimensioned to the centers of the openings, it is easiest in laying off to estimate from the center each way rather than to estimate total width.
After these openings are made, the frame of the house may be covered with sheathing, or the roof may be framed; both orders of procedure are common.
CHAPTER III
Roof Frame: Square Cornered Buildings
15. Roof Framing.—The problem of framing the various members of a roof is not a difficult one provided the underlying principles are understood, and dependence placed upon this understanding rather than upon mere knowledge of what figures to use upon the square to get the cuts, without knowing why those figures are used. An effort will be made in this treatment to indicate the "why."
GABLE HIP SHED GAMBREL
Fig. 39. Roof Types
In [Fig. 39] are illustrated four types of roof. Figs. [40], [41], and [42] illustrate the rafter forms and the names of the various cuts to be made in framing the members to place. The common rafter, it will be seen, has three cuts—plumb or ridge cut, seat or heel or plate cut, and end cut. The hip, valley, and jack have four cuts each; a side cut or cheek cut is possessed by each in addition to the three cuts belonging to the common rafter.
Before any rafter can be framed, the rise and run of the common rafter, in other words, the pitch of the roof, must be known.