Full Product Manual

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 Ice & Water Shield
®
underlayment
directly over the old Grace underlayment in retrot applications
following the standard membrane
application procedure.
Precautions & Limitations
• Slippery when wet or covered by frost.
• Consistent with good roong 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.
Cover within 30 days.
• Place metal drip edges or wood starter shingles over the
membrane.
• 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.
• Certain product applications are prohibited in hot desert areas
in the southwestern United States. Check with your Grace
Construction Products representative.
• Check with the manufacturer of the metal roong system for
any special requirements when used under metal roong. Do
not install directly under roof coverings especially sensitive to
corrosion, such as zinc, without providing proper ventilation.
• Do not install under copper, Cor-Ten
®
, or zinc metal roong in
high altitudes. These roofs can reach extremely high tempera-
tures due to the low reectivity, high absorption, and high
conductivity of the metals. Use Grace Ultra™ underlayment
for these roof types. Check with your Grace Construction Prod-
ucts representative.
• Provide proper roof insulation and ventilation to help reduce
ice dams and to minimize condensation. Grace Ice & Water
Shield
®
membrane is an air and 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 asphaltic odor, do not apply where the
membrane is exposed to interior living space. Refer to product
literature for more complete information.
• Not compatible with EPDM or TPO; use Grace Ultra™ under-
layment for tie-ins (refer to Technical Letter 5, Chemical
Compatibility).
• Not compatible with polysuldes, exible PVC, or high
concentrations of resin (pitch). For more information, refer to
Technical Letter 5.
Code Compliance
Grace Ice & Water Shield
®
roong underlayment meets the
following standards:
• Underwriters Laboratories Inc. Class A re classication under
ber-glass shingles and Class C under organic felt shingles (per
ASTM E108/UL 790)
• Underwriters Laboratories Inc. Classied Sheathing Material
Fire Resistance Classication with Roof Designs: P225, P227,
P230, P237, P259, P508, P510, P512, P514, P701, P711, P717,
P722, P723, P732, P734, P736, P742, P803, P814, P818, P824
• Miami-Dade County Product Control Approved. Report NOA
12-1115.02
• Florida State Approval Report No. FL289-R3
Ice Dams
Wind-Driven Rain
37
Water from melting
snow over the heated
portion of the house runs
down the roof.
It freezes at the cold eave
and an ice dam begins
to form preventing
drainage.
As the ice dam grows,
water is trapped behind
it and backs up under the
shingles. Eventually it
reaches the roof deck and
leaks through, damag-
ing the interior of the
structure.
Grace Ice & Water
Shield
®
underlayment
resists this leakage
because of the seal
around the fasteners,
ability to make watertight
laps, and the membrane’s
bond to the deck.
Sloped roofs are not
waterproof. ey protect
structures by shedding
rain water.
Storm-driven winds can
cause sloped roof cover-
ings to li. Rain can then
be easily driven under
the roof covering directly
to the unprotected roof
deck where it causes
leaks and damage to the
interior of the structure.
Grace Ice & Water
Shield
®
roong underlay-
ment applied beneath
the sloped roof covering
helps prevent wind-
driven rain from entering
the structure.