MIL-HDBK-1001/SA
perimeters and at openings. Such anchorage serves several purposes:
a) To prevent stress concentration at flashings, which could either split or pull loose from their backings and become vulnerable to puncture. (Loose-laid systems receive maximum membrane tensile forces at perimeters and other terminations, according to field strain tests);
b) To restrain contraction in materials subject to long-term shrinkage;
drainage.
c) To reduce membrane wrinkling which can obstruct
6.3 Design Requirements/Considerations
6.3.1 Single-Ply Roofs. For roofs on new facilities (Refer to Section 10 for reroofing):
a) Require minimum 1/2 inch per foot (4 percent)
slope, 2 inch per foot (17 percent) maximum slope for loose-laid,
ballasted systems.
b) Review material properties, limitations, advantages and disadvantages, and past performance of all systems under consideration (check 10-year performance in your geographical location);
c) Determine wind and fire resistance during this preliminary survey. Consult Single Ply Roofing Institute (SPRI) Wind Design Guide for Ballasted Single-Ply Roof Systems Single- Ply Roofing. Ballasted systems should not be specified in coastal areas;
d) Check substrate for suitability: for sheet membranes, suitable substrates are structural concrete (cast-in- place and precast), lightweight insulating concrete with low moisture content, plywood, and rigid insulation board; for fluid- applied membranes, suitable substrates are structural concrete (cast-in-place and precast) and sprayed-in-place polyurethane foam;
e) For cast-in-place concrete decks, check concrete curing agents to ensure compatibility with synthetic membranes. Some curing agents can cause poor adhesion or even premature deterioration of the membrane;
24
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business