1. Design and approvals also take time
Before construction, surveys, studies, design development, coordination, budgeting, revisions and permits may be required. Ignoring this phase produces schedules that look short but do not represent the complete process.
2. Preconstruction and critical procurement
Contracting, supplier selection and orders for custom-fabricated items should be planned before they are needed. Windows, cabinetry, equipment or imported finishes can have lead times that affect the critical path.
3. Sitework, foundations and structure
Earthworks, foundations and structure depend on terrain, weather, access and construction system. Design changes are particularly expensive at this stage because they affect work that is already built or about to be built.
4. Building services and enclosure
Electrical, plumbing and other systems must progress in coordination with walls, roofs, façades and ceilings. Unresolved clashes often surface here and can disrupt the sequence.
5. Finishes and commissioning
Finishes involve many simultaneous trades and require quality control. A house may look “almost complete” for several weeks while details, tests, corrections, cleaning and handover are completed.
6. A useful schedule must be updated
The program is not a document to file away. It should be compared with actual progress, used to identify deviations and actions, and linked to procurement and resources. Ongoing control is more useful than a final date with no follow-up.
A responsible schedule is built from defined scope, sequence, productivity, procurement and contingencies—not from a fixed months-per-square-meter rule.