DIYbanter - View Single Post - Chalk line

George E. Cawthon

wrote:
wrote:

(just hauling the shingle bundles a hundred yards from the
car and then up to the roof about did me in already this morning,
though).

If you ever attempt a larger roofing job, seriously consider rooftop
delivery of the shingles and tar paper. The savings in medical bills
alone can make it worthwhile.

My 1st roofing job was a reshingling, and since the original shingles
were aligned about perfectly, I didn't have to lay down chaulk lines.
But when reshingling it's important to overlap, or "butt up," the new
shingles correctly over the old ones to minimize the amount of empty
space each shingle spans and therefore the sag. This is why the
instructions say to cut the starter course of shingles to the same
width as the tab exposure rather than simply nail down whole shingles
with the tabs facing upward. If the overlap is done wrong, the new
shingles will develop a bend where they sag.

My 2nd attempt at roofing was over bare plywood decking, and I had to
redo it since I originally laid down only horizontal chaulk lines but
not vertical ones. The alignment looked fine to me while I was on the
roof, but from the ground it was a completely different matter. So
chaulk lines are a good idea.

Why would one ever put down vertical chalk lines?
If the alignment of slots is off, the installer is
cutting the starter shingle for each row
incorrectly. Starters should always be cut at the
slot or midway between slots (unless one is into
some fancy pattern. Anyway, the wrapping on each
bundle gives all the instructions.

It is a shed so there should be no dormers, just a
straight shot.