Instructions / Assembly

©2016 GAF 8/16 gaf.com • 1-800-ROOF-411
M-WELD
™
STANDARD M-DRAIN
™
(2 OF 2)
M-Drain
™
New Construction Installation:
1. Install base sheet as required by manufacturer’s
specifications to existing drain leader.
2. Select appropriate size M-Drain
™
to match the
plumbing pipe. Use a flexible coupling to con-
nect the M-Drain
™
to the plumbing pipe.
3. Choose appropriate M-Drain
™
material:
• For heat-welded membranes, use APP flashing
material.
• For hot mop or cold-applied membranes, use
SBS flashing materials.
4. Installations with APP membranes:
• Heat the bottom of the M-Drain
™
flashing to a
glossy sheen. Insert the drain (expandable seal
fully compressed) into existing drain leader, until
the two heated surfaces fit flush. While torch-
ing, work the flashing with a trowel until a 1/4" (6
mm) to 3/8" (9 mm) bleed-out occurs around the
outside of the flashing.
• The tape will expand to seal off the M-Drain
™
to
the drain pipe.
5. Installations with SBS membranes:
• Follow same procedures as for APP, except set
M-Drain
™
in hot asphalt or SBS adhesive.
6. Install field sheet per manufacturer’s specifica-
tion over installed M-Drain
™
. Use the bottom of
the strainer cap provided as a template to cut a
hole in the field membrane.
7. Install strainer cap by lining up the tabs, pushing
down, and twisting cap into place.
M-Drain
™
Retrot Installation Instructions:
1. Before you begin installation:
• Be sure that the “old” drain pipe is as clean as
possible.
• Remove cellophane tape around black expand-
ing seal of retrofit M-Drain
™
.
• Remove and discard existing gravel guard,
strainer, and studs.
2. Install base sheet as required by manufacturer’s
specifications to existing drain leader.
3. When inserting M-Drain
™
into existing pipe or
drain bowl, choose an M-Drain
™
1/2" (13 mm)
smaller than the inside diameter of the existing
opening.
4. Choose appropriate M-Drain materials:
• For heat-welded membranes, use APP flashing
material.
• For hot mop or cold-applied membranes, use
SBS flashing materials.
5. Installations with APP membranes:
• Heat the bottom of the M-Drain
™
flashing to a
glossy sheen. Insert the drain (expandable seal
fully compressed) into existing drain leader, until
the two heated surfaces fit flush. While torch-
ing, work the flashing with a trowel until a 1/4" (6
mm) to 3/8" (9 mm) bleed-out occurs around the
outside of the flashing.
6. Installations with SBS membranes:
• Follow same procedure as for APP, except set
M-Drain
™
in hot asphalt or SBS adhesive.
7. Install field sheet per manufacturer’s specifica-
tion over installed M-Drain
™
. Use the bottom of
the strainer cap provided as a template to cut a
hole in the field membrane.
8. Install strainer cap by lining up the tabs, pushing
down, and twisting cap into place.
Note: Sufficient roof drainage is essential for good roof performance and to avoid overloading the roof
under heavy rainfall conditions. Ensuring that the size and number of drains is adequate for the roof area
and location is the responsibility of the building owner or their roofing consultant.