Full Product Manual
roll. Stop frequently to press the membrane in place with heavy
hand pressure. When nished with the roll go back to the begin-
ning, reroll and pull the remaining release paper from the material,
nishing the installation.
Consistent with good roong practice, install the membrane such
that all laps shed water. Always work from the low point to the
high point of the roof. Apply the membrane in valleys before the
membrane is applied to the eaves. Following placement along
the eaves, continue application of the membrane up the roof. The
membrane may be installed either vertically or horizontally.
Use smooth shank, electroplated galvanized nails for fasten-
ing shingles. Hand nailing generally provides a better seal than
power-activated nailing. If nailing of the membrane is necessary
on steep slopes during hot or extreme cold weather, backnail and
cover the nails by overlapping with the next sheet.
Extend the membrane on the roof deck above the highest
expected level of water back-up from ice dams and above the
highest expected level of snow and ice on the wall sheathing on
vertical side walls (dormers) and vertical front walls for ice dam
protection. Consider a double layer of membrane in critical areas,
such as along the eaves or in valleys and in climates where severe
ice dams are anticipated. Apply the membrane to the entire roof
deck for wind-driven rain protection. Apply a new layer of Grace
Ultra
™
underlayment directly over the old Grace underlayment in
retrot applications following the standard membrane application
procedure.
Precautions & Limitations
• Slippery when wet or covered by frost.
• Consistent with good roong practice, always wear fall protec-
tion when working on a roof deck.
• Release liners are slippery. Remove from work area immedi-
ately after membrane application.
• Do not leave permanently exposed to sunlight. Maximum
recommended exposure is 60 days.
• Place metal drip edge or wood starter shingles over the
membrane.
• Place metal drip edges or wood starter shingles over the
membrane (refer to Technical Letter 15, Roof Eave Applica-
tion).
• Do not fold over the roof edge unless the edge is protected by a
drip edge, gutter, or other ashing material.
• Do not install on the chamfered edges of wood plank.
• Do not install directly on old roof coverings.
• Check with the manufacturer of the metal roong system for
any special requirements when used under metal roong. Do
not install directly under roof coverings especially sensitive to
corrosion, such as zinc, without providing proper ventilation.
• Provide proper roof insulation and ventilation to help reduce
ice dams and to minimize condensation. Grace Ultra
™
under-
layment is a vapor barrier.
• Repair holes, shmouths, tears, and damage to membrane with
a round patch of membrane extending past the damaged area 6
in. (150 mm) in all directions. If fasteners are removed leaving
holes in the membrane, they must be patched. The membrane
may not self-seal open fastener penetrations.
• Do not install fasteners through the membrane over unsup-
ported areas of the structural deck, such as over the joints
between adjacent structural panels.
• Due to its slight rubber-like odor, do not apply where the
membrane is exposed to interior living space.
• Compatible with EPDMs (refer to Technical Letter 5, Chemi-
cal Compatibility). Also for use in tie-ins in EPDM with other
Grace underlayments.
• Not compatible with polysuldes, exible PVC or high
concentrations of resin (pitch). For more information, refer to
Technical Letter 5.
Standard Compliance
Grace Ultra
™
meets the following standards:
• ICC ESR-1677 approval according to AC-48 Acceptance Crite-
ria for Self-Adhered underlayments used as Ice Barriers
• Underwriters Laboratories, Inc. R13399 Class A re classica-
tion under berglass shingles and Class C under organic felt
shingles
• Underwriters Laboratories, Inc. Classied Sheathing Material
Fire Resistance Classication Design Numbers P225, P227,
P230, P237, P259, P508, P510, P512, P514, P701, P711, P717,
P722, P723, P732, P734, P742, P824
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