Construction project phases: from concept to as-builts

A construction project moves through standardised phases, each with its own deliverables and level of detail. Knowing them means speaking the same language as the design team and securing your schedule. Here's a quick tour from a technical-studies angle — French phase names are widely used, with equivalents given.

Design phases

Concept / survey (ESQ / DIAG) — sets the intentions and existing conditions. Schematic design (APS) — the main technical principles and footprints are fixed. Design development (APD) — sizing, materials and estimates are refined. Technical design (PRO) — studies are complete, ready for detailed pricing.

Tendering

Tender package (DCE) — the full dossier goes out to bid. Contract assistance (ACT) — bid analysis and contract finalisation.

Construction phase

Shop drawings / review (EXE / VISA) — execution studies are produced then reviewed by the design team. Site supervision (DET) — site monitoring, meetings, payment applications. Handover assistance (AOR) — support for acceptance operations.

Handover

As-built dossier (DOE) — the final « as-constructed » file, with record drawings, manuals and warranties. It's the building's technical memory.

Why it matters for your schedule

Each phase conditions the next and imposes its deliverables. A clear MEP schedule aligns its milestones with these phases: that's what lets you anticipate deliverables, coordinate trades and avoid cascading delays.