bitumen membrane manufacturer.] Cut at a 45 degree angle across selvage
edge of cap membrane to be overlapped in end lap areas prior to applying
overlapping cap membrane. [Apply matching granules in any areas of
[bitumen][adhesive] bleed out while the [asphalt is still hot][adhesive is
still tacky].] Minimize traffic on newly installed cap sheet membrane.
[3.3.6.2
Backnailing of Cap Sheet
**************************************************************************
NOTE: Include this paragraph for roof slopes
greater than or equal to 1:6 (2 inches per foot).
Coordinate with insulation Section 07220 and nailer
requirements Section 06100 to allow for backnailing
of the membrane.
**************************************************************************
Unless otherwise recommended by the modified bitumen membrane manufacturer
and approved by the Contracting Officer, provide minimum 90 mm (3-1/2 inch)
wide nailing strips matching insulation thickness and applied perpendicular
to roof slope for backnailing of roof membrane. Space nailing strips as
recommended by the membrane manufacturer, but not exceeding 5 meters (16
feet) on center unless approved otherwise by the Contracting Officer.
Coordinate the nailer installation with insulation requirements. Install
the modified bitumen cap sheet to provide for end laps at nailer locations.
Nail the modified bitumen cap sheet at the end lap area across the width
of the sheet. Nail within 25 mm (1 inch) of each edge of the sheet and at
200 mm to 215 mm (8 to 8-1/2 inches) on center across the width of the
sheet in a staggered fashion. Nails shall have 25 mm (1 inch) diameter
metal cap or be nailed through 25 mm (1 inch) diameter caps. Cover nails
by overlapping adjacent upslope sheet at the end lap area.
]3.3.7
Membrane Flashing
Apply two-ply modified bitumen strip flashing and sheet flashing in the
angles formed where the roof deck abuts walls, curbs, ventilators, pipes,
and other vertical surfaces, and where necessary to make the work
watertight. Apply membrane flashing in accordance with the roof membrane
manufacturers printed instructions and as specified. Cut at a 45 degree
angle across terminating end lap area of cap membrane prior to applying
adjacent overlapping cap membrane. Press flashing into place to ensure
full adhesion and avoid bridging. Ensure full lap seal in all lap areas.
Mechanically fasten top edge of modified bituminous base flashing 150 mm (6
inches) on center through minimum 25 mm (1 inch) diameter tin caps with
fasteners of sufficient length to embed minimum 25 mm (one inch) into
attachment substrate.[ Apply matching granules in any areas of
[asphalt][adhesive] bleed out while the [asphalt is still hot][adhesive is
still tacky].] Apply membrane liner over top of exposed nailers and
blocking and to overlap top edge of base flashing installation at curbs,
parapet walls, expansion joints and as otherwise indicated to serve as
waterproof lining under sheet metal flashing components. Metal flashing
are specified under Section 07600 FLASHING AND SHEET METAL.
3.3.7.1
Membrane Strip Flashing
Set primed flanges of metal flashings in full bed of modified bituminous
cement material and securely fasten through to attachment substrate.
Strip-in with membrane flashing so that strip extends not less than 100 mm
(4 inches) beyond outer edge of flange. Where multiple membrane stripping
plies are installed, extend each additional stripping ply minimum 100 mm (4
SECTION 07550
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