Installation Instructions

StormMaster Slate General Instructions
Atlas Roofing
combination of vents at the ridge area and eave areas should be used. All roof structures,
especially mansard and cathedral type ceilings, must have complete flow through ventilation from
eaves to ridge. FHA Minimum Property Standards require 1 square foot of net free attic vent area
for every 150 feet of attic floor area; or one square foot per every 300 square feet, if vapor barrier
is installed on the warm side of the ceiling, or at least one half the ventilation area is provided near
the ridge.
3.) ROOF DECK
These instructions are for the application of Atlas asphalt shingles to nominal 7/16" thick American
Plywood Association (APA/TECO) rated, code approved plywood, OSB decks or minimum 3/4" actual
thickness wood decks. The plywood or non-veneer (OSB) decks must comply with the roof deck
specifications of APA/TECO. Solid wood decking must be well seasoned, not over 6" (nominal) width,
and fastened securely to each rafter. The deck surface must be clean, bare, gap free and flat.
StormMaster® Slate shingles must not be applied to any surface other than roof deck types
described here. Atlas also honors its Shingle Limited Warranty when Atlas shingles are installed on
the Atlas CrossVent® Nailable Insulation panels. Atlas will NOT be responsible for the performance
of its shingles if applied directly to non-vented, insulated decks composed of perlite board, plastic
foam, fiberboard, gypsum plank, lightweight concrete, cementitious wood fiber, or similar materials
or to any decks with insulation installed directly to the underside of the decking, with the exception
of CrossVent® Nailable Insulation. Spray foam insulation applied directly to the bottom of the
decking will void the warranty. Atlas shingles may be installed over a roof system containing a
radiant barrier material if: 1. the required full, flow through ventilation is maintained directly under
the decking material in all cases, 2. the radiant barrier material is highly vapor permeable ( > 2
perms), and, 3. the radiant barrier is installed on the underside of or below the decking – not used
as an underlayment above the decking. Spray-on types of below deck vapor permeable radiant
barriers will be considered only on a job by job basis, and only if tests confirm > 2 perms or greater
vapor permeability.
4.) UNDERLAYMENT
Atlas highly recommends the use of high performance, ASTM 6757 compliant - Gorilla Guard® or
Summit® proprietary underlayment products for long term roof system performance and
WeatherMaster® Granular, self-adhering, waterproofing underlayment for critical areas, such as
valleys and eaves. Atlas does not approve the use of any self-described, metalized or metal
containing category of “Radiant Barrier”, as an asphalt shingle underlayment installed above the
deck. Use of these types of radiant barrier would void the shingle warranty. Underlayment must be
applied flat and unwrinkled. Building codes vary with geographic areas, and the installation must
comply with local building codes or shingle manufacturer’s requirements, whichever is stricter.
Shingles should be applied as soon as possible after the application of organic underlayment felt,
which is not intended for prolonged exposure. Atlas recommends that the shingles be applied the
same day as the felt underlayment application to avoid wetting and wrinkling. If an underlayment is
used for prolonged dry-in, Atlas recommends Summit® Synthetic Underlayment as the dry-in
underlayment, for up to 6 months exposure.
Standard Slope Application: Proper application requires that a single layer of approved
underlayment be applied to decks with slopes of 4” per ft. or greater and consistent with all
applicable building codes. This approved underlayment is a required roof assembly component to
maintain a Class A fire rating of the deck assembly. Install underlayment over the entire deck,
parallel to the eaves, overhanging 1/4” to 3/8”, with fasteners placed 2” from the deck edge, 12”
O.C. across the lower edge and with 2” overlap parallel to eaves and with 4” min. end lap, parallel
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