📋 Estimating / BOQ · 6 min read
Preliminaries and General Requirements in a BOQ
Preliminaries are where thin bids get thinner and where realistic bids protect themselves. They deserve a proper build-up, not a percentage.
What’s in it
| Group | Examples |
|---|---|
| Management & staff | Project manager, engineers, foremen, safety officer, QS, admin |
| Temporary facilities | Site office, stores, mess, toilets, fencing, signage, hoarding |
| Temporary services | Power, water, telecoms, drainage, lighting |
| Common plant | Tower/mobile crane, hoist, pumps, generators, small tools pool |
| Access & enabling | Scaffolding (if not in trades), site roads, laydown |
| Safety & environment | PPE, barriers, dust/noise control, spill kits, first aid |
| Compliance | Permits, testing, surveys, as-built documentation, handover |
| Commercial | Insurances (CAR, third-party), performance bond, retention bond |
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Time-related vs fixed
- Time-related — cost scales with the programme: staff salaries, office and plant hire, security. Price per week/month × duration.
- Fixed / one-off — mobilisation, setting up and removing facilities, final clean, demobilisation. Price as lump sums.
Splitting them this way makes extension-of-time claims and value-engineering assessments straightforward.
Pricing method
Preliminaries = Σ(time-related rate × duration) + Σ(fixed lump sums)
Cross-check the total against 8–15% of the works value — outside that band, something is missing or double-counted.
📋 Using EngEst Pro
EngEst Pro’s Site Overhead tracker itemises preliminaries — supervision, temporary facilities, utilities, safety, equipment, permits, insurance — as time-related and fixed costs that roll into the Bid Summary.
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