Shingles. (A.) In shingling a roof, the shingles should be laid from 4" to 5" to the weather; the steeper the pitch, the greater the exposure which may be allowed. A quarter pitch roof should bo laid with an exposure of from 4" to 4¼" to the weather; a third pitch from 4¼ to 4.½"; and a half pitch roof from 4½" and 4¾". The distance should in no case be more than 5", as each shingle should lap over the two courses below it, as at a. Fig. 118, and at w, Fig. 119 A 16" shingle would not permit this if more than a 5" lap were allowed.
It is necessary that the finish of the eaves, or the outside members of the cornice, should be in place before the lowest course of shingles is laid. This course should be laid double, as shown. This is done by fastening a shingle at each end of the roof, and tacking one every eight or ten feet, with the desired projection, generally about 1½". A chalk line is then stretched, supported by these shingles, and the lower course laid to it. The joints of all courses should be broken at least ¾". By this is meant that the joint of the upper course should be at least ¾" from the nearest one of the course below, as at c, Fig. 118. It is good practice to break the joints of two courses as far as possible. A shingle over 8" wide should be divided in the middle, and laid as two shingles, or it may split over the joint of the course below after it has been exposed to the weather.
Fig. 118. - Shingling A Rook.
Two 4d. nails should be used in each shingle, and should be put in not less than 9" or 10" from the butt, or thick end, for if a joint or a nail hole in a shingle comes over a nail in the course below, rust may cause a leak here before the roof needs repairing elsewhere. Such a leak will be difficult to locate.
If the shingles are very dry they should be wet thoroughly before laying, or laid with the joint at least 1/8"open; otherwise they will buckle and split when wet by the rain.
If the best results are desired, the shingles should be nailed with cut nails, which do not rust out so quickly as wire nails; unless used in a damp locality the wire nails prove satisfactory.
There are two methods of shingling above the lowest course; one is to tack a straight edge to the course below, and lay the next course against it, as shown at d, Fig. 118.
Fig. 119. - Scaffolds for Shingling.
A number of shingles may then be laid upon the roof and nailed rapidly.
Another way, which is preferred by many, is to make a chalk line mark; by this method, as the shingles are laid one at a time, two courses may be carried along together.
Care must be used that the joints between the shingles be kept square with the eaves; if the butts are not square, the worst of them should be made so with a saw.
The scaffolding for finishing down the outside and putting on the cornice should be put up to prepare for shingling, as it may be used to advantage in laying the lower courses, and in working around the roof.
Some workmen lay the lower courses from above, and in repair work it is often better to do this, than to go to the expense of a staging or scaffolding.
There are numerous devices for shingling-scaffolds, or supports upon the roof, two of which are shown in Fig. 119. That shown at a is a very simple device, being nothing but a piece of 2" X 4", with pieces of board about 20" long nailed upon it about six feet apart, through the upper end of which, at z, a couple of nails are tacked into the roof. Shingles are used by some workmen for this purpose, in place of the 20" boards. This form is preferred by many to the more elaborate bracket shown at b. Several of these are placed at convenient distances, and a board laid across them, providing a much safer foothold than does the one above described.
(B.) We will discuss three methods of shingling hips. Tin shingles are used in two ways, as shown in Fig. 120, a and b. In nailing the hip shingles laid by either of the two methods, it is necessary that nails should be driven near the points to resist the tendency to warp.
Tin shingles should correspond in shape to that of hip shingles; they should be at least 7" wide, and long enough to reach well under the tin shingles of the course above, as at w. At a, the tin shingles are laid so that the lower end will just be covered by the hip shingle of the course above; this method is not so serviceable as that illustrated at b, as the short grain of the hip shingles at z will in time split off, and the hip be destroyed, though the former makes the better-looking hip when first laid. In b, the tin shingles are laid over the hip shingles, flush with the lower edge of each course; this protects the short grain, and is a very satisfactory way of finishing a hip. In all cases, care should be used that the line of the hip is kept perfectly straight from the eaves to the peak. Some workmen make their tin shingles long enough to allow the bottom end to be turned down the thickness of the butt of the hip shingle, and drive nails through the tin into the butt. This holds the lower end of the tin shingle without any nails directly through it, which should be avoided if possible, as the action of the weather is apt to make a leak where a nail is unprotected. The top end of the tin shingle should be held by driving nails where they will be covered by the hip shingle of the course above.
Fig. 120. - Hip Shingling; Methods 1 and 2.
In Fig. 121 is shown the third method of hip shingling, the short grain of the above methods being done away with. The tin shingle z may be cut square upon both ends and laid under the hip shingle out of sight, as at a, the hip shingles forming a row of raised shingles along the hip. In this case, the hip shingles may, if necessary to hold them down, be nailed at the butt end, d as the upper end of the "sight" at 6, or that part of the shingle "to the weather," is not so thick as the lower end of the course it fits against, as at c, which may leave a space between the back side of the hip shingle, d, and the face side of b, unless the upper shingle is nailed down to a joint. This should be avoided if possible, and the nails driven where the hip shingle of the next course will cover them. In most cases these nails will be sufficient.
The hip joint may be mitered, as at e, or lapped, as at f.
The hip is less apt to leak than any other place upon the roof, as the water runs away from it; but since it is so prominent, the work should be well done, and all lines from the ridge to the eaves should be straight and parallel.
Fig. 121. - Hip Shingling; Method 3.
(C.) In valley shingling, a strip of tin, lead, zinc, or copper 20" wide should be laid in the valley, as at a, Fig. 122, and nailed only at the extreme edges. The best shingles should be laid in a valley, allowing a wash of at least 6", as at b, except in the valleys of small roofs, dormer windows, etc., which may have sheet metal 16" wide, and a wash of 4 ½".
Shingles should not be laid in a valley beyond the place where those of the course above will meet them; for instance, course c need not be continued beyond d, where it meets the course under hip shingling. This is used by many, but it does not stand so well as a valley with a wash, as it does not dry out so readily.
■ above. This leaves a triangular space, def, in which the shingles do not lie closely against the tin, but which allows the air to enter under the valley shingle of course g, thus assisting the shingles in drying out, and also making it unnecessary to drive nails through the tin, as would be required if the courses were carried out to the valley. The valleys usually leak before any other place in the roof, as they are apt to be more in the shade, and to have less circulation of air; the snow and leaves find lodgment there, and are often retained after the rest of the roof has dried out.
Another method is to lay the valley shingles close, using a tin shingle under each course, an application of method 1
Fig. 122. - Valley Shingling.
(D.) In repairing a split shingle upon a roof, a tin shingle about 3 ½" X 7" may be pushed under the split as in Fig.
123; by turning up the upper corners, as at a, the tin shingle will be held in its place. If there is a serious leak, the place should be reshingled; the old shingles should be torn off by means of a thin piece of steel shaped as in Fig. 124, and from 24" to 30" long, which may be thrust under the shingles to cut the nails by means of the edges b. Unless this is done, it is difficult to stop the patch upon the upper end.