Installation Instructions

StormMaster Slate General Instructions
Atlas Roofing
to the rake. Underlayment end laps shall be staggered 6 feet apart from the adjacent courses.
Corrosion-resistant drip edge should be placed over the underlayment at the rake and beneath the
underlayment at the eaves.
Low Slope Application: 2:12-4:12 (51mm/305mm) on slopes of 2" to 4" rise per foot, a double
layer of approved underlayment over the entire deck surface is required. Starting with a 19" wide
strip at eaves and overhanging the eaves 1/4" to 3/8", cover the first 19" course with a full 36" wide
strip. Expose the first course 17" and continue up the deck with 36" wide strips, lapping each
course 19" over the preceding course - providing a 17" exposure. End laps for low slopes shall be of
at least 12" overlap and staggered 6 feet apart. Install drip edge over the underlayment at the rake
and beneath the underlayment at the eaves. WeatherMaster® Granular is highly recommended as
the underlayment for Low Slope (2" in 12" to 4" in 12") to cover the entire deck prior to installing
shingles.
5.) FLASHING
All flashing should be in place as shingles are installed. Cap flashings of sheet metal and base
flashings of metal or mineral surfaced roll roofing should be used at vertical surfaces such as
chimneys, skylights, vents, walls, etc. All flashings should be sealed with asphalt plastic cement.
Consult the Residential Asphalt Roofing Manual published by the Asphalt Roofing Manufacturers
Association (ARMA) for details concerning specific methods and types of flashing installation.
6.) ICE DAM PROTECTION
Eave and rake edge waterproof flashings must be installed per local building codes and where there
is a possibility of icing along the eaves and rake edges causing a potential for ice damming and a
backup of water. Atlas’ WeatherMaster® Granular Underlayment, or equivalent must be applied
directly over the decking according to application instructions provided with the product, and local
building codes. The waterproof flashing material must extend up the roof at least 24" beyond the
interior warm wall line, and in areas of severe icing, at least up to the highest water level expected
to occur from ice dams. If the overhang requires flashing wider than 36", the horizontal lap must be
located on the overhang area and cemented or sealed. End laps must be 12" (minimum) and
cemented/sealed. WeatherMaster® Granular Underlayment, as supplied by Atlas, is recommended
as the first layer of Ice Dam Protection. WeatherMaster® Granular Underlayment conforms to ASTM
D-1970.
7.) VALLEYS
Open Valley: Over felt underlayment or WeatherMaster® Granular Underlayment apply a 36”
wide mineral surface roll roofing (with granular side up) or smooth roll roofing centered in the
valley. Install 16” wide minimum copper flashing (or equivalent) also centered in valley. Secure the
copper flashing every 24” along both edges either with copper cleats or large head copper nails
with the shanks immediately adjacent to the copper edge. Overlaps in the copper must be a
minimum of 12”.
Strike chalk lines on each side of the copper valley 3” from the center line. As shingles are applied,
trim them to chalk lines and, to direct water into valley, cut 2” diagonally off upper corner of
shingles adjacent to chalk line. Set valley edge of each shingle in a 3” wide band of asphalt plastic
cement meeting ASTM D-4586 and nail no closer than 6” from valley center line. See Diagram #1.
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