To finish gutters, fasten and carefully cement with the pitch or tar or
prepared composition the edge of the strip about half-way to the gutter.
Bring the other edge onto the roof, then lay the next strip over this
strip so that it will overlap at least two inches. Proceed to lay the
balance of the roofing in the same way. Never nail the middle of the
strips; nail only along the edges. The end strips should always be lapped
over the edges of the roof and fastened (Figs. 297 and 299).
Before fastening laps paint a two-inch strip with the tar or pitch cement
which comes with all patent roofing in order to stick it to the lower
strip of roofing and to make a tight joint when put in place.
Do not drive nails carelessly or with too much force and be sure the cap
fits snugly against the roofing. If nails go into holes or open cracks, do
not remove them but thoroughly cement around them. Allow six inches for
overlaps for joints where one strip joins another (Fig. 299, _B_). Be sure
that two strips of roofing never meet at the ridge leaving a joint to
invite a leak over the ridge-pole. Examine the diagrams if you fail to
understand the description.