Dow Protected Membrane Roof EN - Manual (Page 8)

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7
Components
S T Y R O F O A M ™ E X T R U D E D P O L Y S T Y R E N E I N S U L A T I O N
Function
Provide thermal properties:
STYROFOAM ™ extruded poly-
styrene insulation has a high
aged thermal resistance (R-value)
when compared with competi-
tive roof insulations.
Provide membrane protection:
By installing the insulation over
the membrane, the membrane
is kept at a relatively constant
temperature year-round and
protected from weathering,
mechanical damage and abuse.
Specification
The insulation shall meet
ASTM C578-05 (Type V, VI or
VII depending on the required
properties) or CAN/ULC S701
Type 4.
Install required thickness of
STYROFOAM ™ extruded poly-
styrene insulation unbonded
over the roof membrane. Install
a slip or separation sheet over
the membrane if the membrane
is coal tar or Type 1 or 2 asphalt,
or if required by the membrane
manufacturer.
Butt boards tightly together
with a maximum 3/8" gap
between boards, staggering end
joints. The recommended stagger
between each board is 2'.
However, in cases where boards
have been cut to fit, try and
maximize the stagger where pos-
sible. At a minimum, each board
should have at least an 8" stagger.
When using STYROFOAM
insulation with pre-cut drainage
channels, ensure that the
drainage channel edges are face
down (i.e., on the membrane side).
Bevel edges to fit closely to
cant slopes.
Fit around protrusions and
obstructions with a maximum
3/4" gap to minimize heat loss.
Multi-layer foam installation:
• The bottom layer of insulation
(the layer directly on the
membrane) must be at least
2" thick.
• The bottom layer must be the
thickest or, at minimum, equal
to the top layer (e.g., 3" bottom
and 3" top).
• Lay successive layers of
insulation unbonded or
unadhered.
• Stagger or offset all joints from
those of the underlying layer.
Installation Notes
Protect insulation from physi-
cal damage.
Handle boards carefully to pre-
vent damage during installation.
Always wear protective eye-
wear and gloves when handling
and cutting insulation.
Always store insulation away
from direct sunlight, particularly
when storing for an extended
time. Cover with a light-colored
opaque tarp for protection from
solar radiation. The surface
degradation caused by ultraviolet
(UV) light will have no measurable
effect on the insulating value
unless the deterioration is
allowed to continue until actual
thickness is lost.
Always check the compatibility
with other products that may
come in direct contact with the
insulation, particularly those
containing solvents. Preventive
care must be taken, such as
allowing the solvents to evapo-
rate, providing a slip sheet or
painting the surface of the insu-
lation with white latex paint.
Always brush off any surface
dust before applying white latex
paint on the insulation.
STYROFOAM ™ extruded poly-
styrene insulation is combustible
and may constitute a fire hazard
if improperly used or installed.
The insulation contains a flame-
retardant additive to inhibit
ignition from small fire sources.
During shipping, storage, instal-
lation and use, this material
should not be exposed to open
flames or other ignition sources.