Parapet
The wall that rises above the roof edge, with flashing and coping on top.
Quick Answer
A parapet is a low wall that extends above the roof surface at the edge of a building or at a change in roof level. It hides roof edges, can serve as a firewall extension and carries flashing and coping. Estimators measure the wall in SF, flashing and coping in LF, and count corners and scuppers.
The Full Picture
NRCA describes a parapet as a permanent barrier extending the wall at the roof's edge, usually by a few feet. It can be part of an exterior wall that continues above the roof edge, or a continuation of a vertical feature such as a firewall. Parapets are common on low-slope commercial roofs and screen rooftop equipment, finish the facade line and support the roof edge detail.
Because a parapet touches several trades, its takeoff splits cleanly. The wall itself is in masonry, framing or concrete, measured in SF of face and sometimes in LF at a set height. The roof membrane runs up the inside face as base flashing, measured in SF or LF by height. Through-wall flashing, counterflashing, coping and any scuppers or overflow openings are separate items. Coping is measured in LF of finished run, with outside corners, inside corners and end caps counted EA. Coping materials in guidance such as the Air Force Facility Standards page on parapets and copings include aluminum, zinc-coated steel, stainless steel, or architectural precast concrete over a through-wall membrane for certain facility groups.
The drawings that define it are the roof plan, wall sections, parapet details, elevations, and the roofing and sheet metal sections in Division 07. Heights vary by project, and changes in roof level create stepped parapets that need their own measurements. Guard function is separate: roof edge fall protection during construction is governed by OSHA, for example top rails set at 42 inches plus or minus 3 inches where a guardrail system is used, so a parapet height does not by itself resolve temporary protection.
Pricing errors come from scope gaps between trades. The mason carries the wall, the roofer carries flashing up to the top, the sheet metal contractor carries coping, and each assumes another picks up the cap flashing, sealant or substrate. Corners, expansion joints, scuppers cut through the wall and returns at roof access are where LF counts and EA counts diverge. A parapet also adds exposed wall area that needs finish or waterproofing, which an envelope takeoff has to capture.
Real Examples
Common Misconceptions
People assume: A parapet is just the same as the exterior wall.
Actually: It is the part above the roof, and it has its own flashing, coping and sometimes scupper details that are not in the wall's field area. NRCA describes it as an extension of the wall at the roof's edge.
People assume: Parapet height is fixed by code or standard.
Actually: Guidance such as the Air Force page on parapets and copings gives no numeric height, and heights come from the design drawings and project requirements.
Does MeltPlan Solve This?
Partially — adjacentParapet perimeters, roof edge lengths and wall face areas come off the plans and elevations, and MeltPlan's takeoff service pulls them with AI and has US-based experienced estimators review and adjust them. Which trade carries coping and cap flashing, and how corners and joints are priced, stays with your estimating team.
Get parapet and roof-edge lengths measured →Frequently Asked Questions
What is a parapet?
A parapet is a wall extension above the roof edge or a change in roof level. NRCA describes it as a permanent barrier that extends the wall, usually by a few feet.
How is parapet coping measured?
In linear feet along the top of the wall, with outside corners, inside corners and end caps counted separately in EA.
Which trades price a parapet?
Typically the wall trade (masonry, framing or concrete), the roofer for base flashing, and sheet metal for coping and cap flashing. Scope sheets should say who carries each part.
Where is a parapet defined in the documents?
On roof plans, wall sections, parapet details and elevations, with materials in the Division 07 roofing and sheet metal sections and the wall trade's section.