ABSTRACT
WORKED EXAMPLE The example is of a contract for the construction of an Airport extension. The contract includes concrete surfaced aprons/runways, surface water drainage, construction of two concrete structures, minor accommodation works and two culverts. The Conditions of contract are ICE Standard conditions; the contract period is 12 months; and the approximate value is £11.0 million. It is assumed that the main Contractor will sub-let bulk earthworks and landscape, fencing, concrete surfacing, signs and lighting as well as waterproofing to structures. It is also taken that all materials are obtained off site (including concrete). The worked example demonstrates a method of assessing preliminary costs and is based on the programme below together with an assessment of general purpose plant (a plant reconciliation is also given). CONTRACTOR'S SITE ONCOSTS - TIME RELATED
Site staff salaries (see programme ) £
£
Agent 54 wks at £1800 97,200
Senior Engineer 54 wks at £1600 86,400
Engineers 76 wks at £950 72,200
General foreman 52 wks at £1000 52,000
Office manager/cost clerk 52 wks at £850 44,200
Timekeeper/Storeman/checker 44 wks at £600 26,400
Admin support 52 wks at £450 23,400
Security guard 52 wks at £500 26,000
Quantity Surveyor 52 wks at £1000 52,000
Fitter 42 wks at £830 34,860 514,660 Site staff expenses (1% staff salaries) 5,146 Attendant labour
Chainman 128 wks at £570 72,960
Driver 52 wks at £610 31,720
Office cleaner (part-time) 52 wks at £165 8,580 113,260 General yard labour
(Part-time involvement in loading and offloading, clearing site rubbish etc.)
1 ganger 10 wks at £610 6,100
4 labourers 40 wks at £580 23,200
29,300
Plant maintenance (Contractor's own plant)
(Fitter included in Site Staff Salaries above)
Fitter's mate 32 wks at £570 18,240
18,240
Carried forward £
680,606
Brought forward
£ 680,606
Site transport for staff and general use
QS/Agent's cars 54 wks at £150 8,100
Engineers' cars (contribution) 130 wks at £90 11,700
Land Rover or similar SWB 54 wks at £360 19,440 39,240 Site transport – Labour 48 wks at £600 28,800 28,800 Transport for labour to and from site NIL Contractor's office rental
Mobile offices (10 staff x 8 m²) = 80 m² 52 wks at £205 10,660 Section offices (2 nr at 10 m²) = 20 m² 52 wks at £50 2,600 13,260 Contractor's site huts Stores hut, 22 m²
52 wks at £56 2,912 2,912 Canteen and welfare huts
Canteen 70 m² (assume 70 men) 52 wks at £180 9,360 Washroom 30 m² 52 wks at £70 3,640 Staff toilets 52 wks at £180 9,360
Site toilets 52 wks at £240 12,480 34,840 Rates
NIL
General office expenditure etc.