INTEESECTIONS OF BOOFS 



65 



K 6t°rc//?/v S ro *+ 

 OveffLffP Z'ro 3" 

 Fig. G6. 



Horizontal flashings are in long pieces ; side flashings may be 

 either in long or short pieces. 



Fig. 65 shows a side flashing in short pieces lapped over each 

 other from 2 to 4 inches. At, and near, the point A, where there is no 

 overlap, a little soldering will be necessary. 



Fig. 66 shows a side flashing which is largely used. The upper part, 

 or apron, is made up of short pieces, while the lower part, or under- 

 flashing, consists of long pieces. This is 

 called a double flashing, since it consists 

 of upper and lower pieces. Note how the 

 tail of each of the short upper pieces is 

 held in a slit cut in the adjoining piece, 

 as at B in the drawing. 



Note that in all side- flashings, edges 

 such as CD, Fig. 65, are not vertical, but 

 overhang so as to exclude rain. 



When a chimney shaft penetrates a 

 roof-slope, the flashing on the upper side 

 of the shaft is formed similarly to that on 

 the lower side, i.e. as shown at HF in 



Fig. 65. It will be evident however, that, in the case of the flashing 

 on the upper side, rain-water would penetrate between the corrugated 

 iron and the flashing HF. This is prevented by laying an extra corru- 

 gated iron sheet with its lower end on top of the flashing HF, and 

 with its upper end inserted below the upper sheet of the next hori- 

 zontal joint further up the roof slope or, it may be, below the ridging, 

 if no horizontal joint intervenes. 



Intersections of Roofs. — Fig. 67 will, if carefully studied, help to 

 make clear the arrangement of the roof timbers and roof-covering at 

 the intersection of two roofs of different span. The drawing is intended 

 to illustrate the intersection of the roofs of the feed-room and cow-byre 

 shown in the frontispiece. 



At the intersection of two roof slopes forming a re-entrant angle, a 

 valley rafter, VK, of special strength (usually 9" by 1|") is erected. 

 Between the valley rafter and the ridge-board run a series of short 

 rafters, JK, known as jack rafters. Along each side of the valley rafter 

 runs a purlin, VP, to support the valley guttering, and to which both 

 guttering and roofing plates are screwed. The valley guttering, in this 



