Rooftop mechanical equipment: curb, structure and membrane

Adding or replacing equipment on a flat/low-slope roof affects loads, opening, membrane upstands, drainage, vibration, condensate and service access.

Decision triage

VERT / GREEN · JAUNE / YELLOW · ROUGE / RED

What the professional checks

The professional checks loads/vibration, opening and curb, anchorage, air barrier/insulation, membrane upstands, drainage/condensate and service access.

Official sources

Sources checked: 2026-08-24

Related path

Continue with the right tools

These links connect this page to the next useful checks and decisions without repeating the full content.

Plan a complete construction projectConnect feasibility, design, permits, concealed work, commissioning and closeout.Open →Check permit triggersPrepare the questions and documents to confirm with the local authority.Open →Check a contractorDocument licence, insurance, scope, payments, changes and warranties.Open →Update a construction costEscalate a historical cost using comparable index values.Open →Prepare pre-delivery reviewRecord documents, enclosure, systems, finishes and deficiencies before closeout.Open →

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