Do not use surface applied cap flashings. See attachment 5. Surface
applied cap flashings have a high rate of failure. Install all cap
flashings in reglets raked in masonry or cut or cast into concrete.
See attachment 6.
Locate vent, stacks and other individual penetrations through the roof
not less than 18 inches apart, and from walls and other vertical
surfaces. See attachment 7. Flashings for vent stacks should be as
illustrated in attachment 8.
Use perimeter roof drains in lieu of interior roof drains when
possible. See attachment 9. If interior roof drains are absolutely
necessary, provide a means of expansion between roof drains and
leaders to allow the roof drain to move with the roof assembly when
subjected to allowable deflection. When this movement is restricted,
it can break flashing connections between the roof drain and roofing
membrane, allowing water to enter.
Elevate metal roof edges to keep metal work above the water line.
See attachments 10 and 11. Do not strip flash metal items longer
than 2 feet into the roofing membrane. See attachment 12.
Install roofing expansion joint covers above the water line. See
attachments 13 and 14.
Where there is potential for deflection of the roof assembly at
abutting non-supporting walls and penetrations, design flashings to
allow for differential vertical movement. See attachments 15, 16 and