Parapet coping and cap installation · Lesson 2 of 4

Parapet coping and cap installation: materials, standards and design constraints

Who governs a coping installation, the RE-3 test, the membrane over the wall top, treated wood and metal compatibility, slope and drips, free movement and joints, why each maker prints its own numbers, and standard piece lengths.

You will be able to: Name the documents that govern a coping installation, explain what ES-1 requires and the 2025 proposed ED-1 revision calls for in the membrane, slope, movement and joints, compare thermal movement with a printed gap, and keep each maker's values with its own system.

10 min · 12 slides · 6 questions

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Slide 1 of 12

Who governs the installation

AFS's Drexel guide pages, which show the sequence, say:

This sequence follows Drexel Metals' published installation guide for the system. The project's specifications, the approved shop drawings and the roofing membrane manufacturer's requirements govern; where they differ, follow them and ask AFS.

Behind a tested system stand ES-1, the test standard, and ED-1, the design standard.

Sources

Glossary

RE-3: The ES-1 test for copings and other roof edges whose exposed top is wider than 4 in: top and face loaded together at 1.73 to 1.
ED-1: SPRI's design standard for roof edge systems on low-slope roofs. This course quotes the revision SPRI proposed in October 2025, and says so wherever it cites it.
ACQ: A treated lumber named in Drexel's coping guides, which isolate all metal parts from ACQ-treated wood with an appropriate membrane. The 2025 proposed ED-1 revision notes that pressure-treated nailers are frequently treated with a solution containing copper.
Tapered coping: A coping whose top is formed with the slope built in; Polyglass sells Polyforza in flat and tapered versions.
Thermal movement: The growth or shrinkage of metal with temperature: coefficient x length x temperature change. The 2025 proposed ED-1 revision calls for edge systems that allow it freely.