Remember, business loves speed. Another way to speed up the process of applying the shingles is to have a cheap, disposable measuring tape that has no other purpose except to be a measuring guide to set the overlap on the shingles.

In order to speed up the installation process, several inexpensive, disposable tapes would be run down the roof that have nothing on them except lines showing the overlap distance that the manufacturer wants for that particular shingle and each line would be numbered.

The installers would run the tapes down the roof and set the first line that has the number one on the bottom edge of the roof and they nail the tape to the roof. This tape is then pulled taught at the top of the roof and nailed there and the number at the top of the tape is noted.

Then another, identical tape would be run down the roof a certain distance away from the first tape. (the distance indicated by the length of the guide bar being used at this location on the roof)

Both tapes are installed identically with the top number matching both tapes. It must be remembered that when the shingles are attached to the roof, the shingles never adhere themselves to the underlayment of the roof but are only held in place by the nails.

Therefore these measuring tapes never need to be removed from the roof because they will be made so inexpensively that their cost is negligible and their only purpose is to set the overlap of the shingles.

These measuring tapes will be so thin that even after years of laying under the shingles, they would not cause any visible lines in the shingles. But having them run down the roof and nailed quickly onto the roof eliminates the need to apply any marks on the roof. They are installed quickly and the installers use them only to set the overlaps by moving the shingle alignment bar up to each line as fast as the alignment bar could be loaded, the shingles nailed down and the bar moved up to the next line and repeated.

It’s just repetition. But it is a safety measure to make sure the lines of shingles are consistently applied as fast as possible, evenly all the way up the roof so that when the installers are at the top of the roof, they don’t need to worry if they have inadvertently applied the rows on a creeping bad angle and now must compensate the rows for esthetic purposes.