Tear-off roof
A re-roofing job consists of applying new roofing material over the existing suface. This is less expensive and easier than a "tear-off" job, which requires that the old roofing be stripped off and hauled away.
(Fig. 1)
Count the Layers: The first step in determining whether or not you can re-roof over the existing surface is to check the rake (the sloped edge) of the roof to derermine how many roofing layers exist. (fig.1)
Remember that drip edge sometimes is applied before re-roofing and may hide evidence of previous layers. Once the number of layers is determined, check local roofing codes for maximum number of roofing layers allowed. The answer depending on the type of roofing materials and the pitch of the roof.
(Fig. 2)
Check for Solid Sheathing: All rotten boards under the old roofing must be replaced. Go into the attic and examine all suspicious spots includ-
ing voids and separating plywood. Check for rot by poking with a screwdriver. If the rot is limited to a few places, you need only remove the old roofing and replace the boards in those spots. If necessary, build up the roofing above the replacement sheathing with extra layers of shingles to make a flush surface for the new roof.
(Fig. 3)
(Fig. 4)
Shake roofs, shingle roofs that have
curled excessively, and old style inter-
locking shingles must be torn off.
Begin at the ridge & work your way down
(this is especially important for wood
shingles so debris does not fall through
the open sheathing. Tear-off wood shingles
or shakes by sliding a crowbar or prybar
undereath & pulling sharply upward. This
loosens several rows at a time.
(Fig. 7)
(Fig. 6)
(Fig. 5)
Save Old Flashing: Remove flashing carefully
so it can be used as a template for new flashing
If old shingles & nails are removed with care,
the flashing canbe reused. In the case of chimney flashing where the upper part may be
embedded in mortar, you may be able to bend
the flashing carefully out of the way rather than
troubling to remove it.
Inspect the Deck: Once you've removed the
roofing, inspect all of the sheathing and replace
broken or rooten pieces with a materials of the
same thickness. On older homes, the sheathing
may be 7/8-inch thick. Plywood sheathing is not
available in thicknesses greater than 3/4 inch.
Use extra layers of felt or roofing materials to
make up the difference.
Placing the dumpster close to the house is the
easiest way to remove the roofing material.
You can slide the roofing material right into
the dumpster.
Charles Copley
Roofing, Inc
