Site Overhead and General Conditions — What to Include
Site overhead is the cost of running the project as distinct from building it. Underestimating it is the most common reason a technically-sound bid loses money.
The categories
| Category | Typical items |
|---|---|
| Supervision & staff | PM, site engineers, foremen, safety officer, surveyor, storekeeper, timekeeper |
| Temporary facilities | Site office, meeting room, stores, mess, sanitation, first-aid room, fencing, signage |
| Temporary utilities | Construction power & connection, water, internet, temporary lighting, temporary drainage |
| Safety & environment | PPE stock, edge protection, barricades, fire points, dust and noise control, erosion control |
| Equipment & plant | Common tools pool, small plant, survey instruments, gensets, water pumps |
| Permits & fees | Building permit, occupancy, utility applications, road-opening, environmental clearances |
| Insurance & bonds | CAR/EAR insurance, third-party liability, workmen’s compensation, performance and retention bonds |
| General | Progress photos, as-builts, O&M manuals, mock-ups, cleaning, handover, demobilisation |
Time-related vs fixed
Salaries, office and plant hire, security, and utilities scale with the programme. Mobilisation, connections, mock-ups, and demobilisation are one-off. Splitting them lets you price an extension of time correctly.
Benchmark
For medium-scale building work, site overhead lands around 8–15% of direct works cost. Fast-track, constrained-site, or remote projects run higher.
EngEst Pro’s Site Overhead tracker itemises every general-conditions cost, separates time-related from fixed, and feeds the total into the Bid Summary with an itemised breakdown the client can see.
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