Whole-life cost model | Features

Whole-life cost summary for three model buildings over 25 years
			40,000 ft2			100,000 ft2			200,000 ft2
	Total cost (£)	Cost £/ft2	% of total cost	Total cost (£)	Cost £/ft2	% of total cost	Total cost (£)	Cost £/ft2	% of total cost

Capital cost	3,536,000			8,566,000			23,600,000
Less capital allowance	328,848			796,638			2,194,800
Sub-total	3,431,653	85.79	11.84	7,769,362	77.69	13.58	21,405,200	114.52	19.19
Occupancy
M&E maintenance	2,142,450	53.56	7.39	3,174,000	31.74	5.18	5,819,000	29.10	4.88
Lifts	55,650	1.39	0.19	111,300	1.113	0.18	166,950	0.83	0.14
Fabric	526,000	13.15	1.81	1,315,000	13.15	2.15	2,630,000	13.15	2.20
Finance	5,136,259	128.41	17.72	12,442,646	124.43	20.32	34,280,464	171.40	28.73
External land	206,412	5.16	0.71	353,205	3.53	0.58	635,250	3.18	0.53
Internal planting	156,870	3.92	0.54	325,290	3.25	0.53	598,986	2.99	0.50
Cleaning	1,262,400	31.56	4.35	3,156,000	31.56	5.15	6,312,000	31.56	5.29
Waste	80,850	2.02	0.28	206,588	2.07	0.34	420,000	2.10	0.35
Electricity	2,385,960	59.65	8.23	5,964,900	59.65	9.74	11,929,800	59.65	10.00
Gas	185,850	4.65	0.64	464,625	4.65	0.76	929,250	4.65	0.78
Water	128,400	3.21	0.44	321,000	3.21	0.52	642,000	3.21	0.54
Reception service	850,080	21.25	2.93	850,080	8.50	1.39	1,275,120	6.38	1.07
Communications	3,224,558	80.61	11.12	4,372,476	43.72	7.14	5,417,341	27.09	4.54
Postroom	398,160	9.95	1.37	770,070	7.70	1.26	833,400	4.17	0.70
Porterage	398,160	9.95	1.37	770,070	7.70	1.26	1,087,600	5.44	0.91
Internal moves	4,915,680	122.89	16.96	12,560,520	125.61	20.52	25,536,000	127.68	21.40
Security	1,605,240	40.13	5.54	3,210,480	32.10	5.24	4,815,720	24.08	4.04
Catering	2,234,498	55.86	7.71	4,730,939	47.31	7.73	5,114,063	25.57	4.29
Management	1,203,750	30.09	4.15	2,006,250	20.06	3.28	3,210,000	16.05	2.69
Replacement	1,890,766	47.27	6.52	4,117,241	41.17	6.73	7,670,912	38.35	6.43
Total	28,987,993	724.70	100	61,222,679	612.23	100	119,323,856	596.62	100.00
Cost £/ft2	724.70			612.23			596.62
Population	308			787			1,600
Cost/head	94,211			77,753			74,577

Comparison of service provision in the three sizes of office
	40,000 ft2	100,000 ft2	200,000 ft2
	308 occupants	787 occupants	1600 occupants
M&E maintenance	All planned and reactive mechanical and electrical maintenance – one resident engineer and a “mate”	All planned and reactive mechanical and electrical maintenance – one resident engineer and a “mate”	All planned and reactive mechanical and electrical maintenance – working site manager, two resident engineers
Lifts	Two hydraulic lifts	Four hydraulic lifts	Six hydraulic lifts
Fabric	All reactive fabric maintenance	All reactive fabric maintenance	All reactive fabric maintenance
External land	Soft and hard landscape maintenance	Soft and hard landscape maintenance	Soft and hard landscape maintenance
Internal planting	Maintenance of internal plants – planting to reception, lift lobbies, corridors and sporadically through office	Maintenance of internal plants – planting to reception, lift lobbies, corridors and sporadically through office	Maintenance of internal plants – planting to reception, lift lobbies, corridors and sporadically through office
Cleaning	Accommodation and window cleaning of offices. Monday to Friday plus periodics	Accommodation and window cleaning of offices Monday to Friday plus periodics	Accommodation and window cleaning of offices Monday to Friday plus periodics
Reception service	Two receptionists Monday to Friday 9am-5.30pm	Two receptionists Monday to Friday 9am-5.30pm	Three receptionists Monday to Friday 9am-5.30pm
Communications	Calls and line rental	Calls and line rental	Calls and line rental
Postroom	One postroom operative Monday to Friday	Two postroom operatives Monday to Friday	Two postroom operatives Monday to Friday
Porterage	One porter Monday to Friday	Two porters Monday to Friday	Three porters Monday to Friday
Internal moves	Based on churn rate of 60%	Based on churn rate of 60%	Based on churn rate of 60%
Security	24-hour security	24-hour security	24-hour security
Catering	Subsidised catering plus corporate entertaining	Subsidised catering plus corporate entertaining	Subsidised catering plus corporate entertaining
Management	One resident facilities manager	One resident facilities manager and assistant	One resident facilities manager and two assistants

25-year occupancy costs for 33 Old Broad Street compared with the 200,000 ft2 model
	200,000 ft2 model £	OBS £	Reason for differences in cost
M&E maintenance	5,819,000	13,825,000	High-tech uninterruptible power supply at Old Broad Street. Also significant plant for enormous atrium
Lifts	166,950	1,100,000
Fabric	2,630,000	1,000,000
Finance	34,280,464	na
External land	635,250	na
Internal planting	598,986	137,500
Cleaning	6,312,000	9,951,136	Higher requirements from merchant banks – prestige clients demand high requirements
Waste	420,000	775,000
Electricity	11,929,800	13,800,000
Gas	929,250	300,000
Water	642,000	500,000
Reception services	1,275,120	1,325,000
Communications	5,417,341	na
Postroom	833,400	4,829,545	Multi-tenancy buildings – therefore more postrooms
Porterage	1,087,600	1,590,909	As above
Internal moves	25,536,000	6,676,136
Security	4,815,720	10,672,727	Merchant banks are extremely security-conscious
Catering	5,114,063	na
Management	3,210,000	9,647,727	Multi-tenancy buildings have greater management requirements
Replacement	7,670,912	7,659,032	Same costs assumed. No information about Halifax available
Total	119,323,856	83,789,714

Detailed specification for 40,000 and 100,000 ft2 buildings
Foundations	Reinforced concrete foundations
Ground-floor slabs	Reinforced concrete floor slabs. Power floated finish
First, second and plant room floor slabs	Precast concrete planks with structural topping or insitu concrete on permanent formwork. First, second and plant room floor slabs give one-hour fire resistance
Structure	Internal steel frame, generally on a 6 and 7.5 × 6 m grid, supporting upper floors, roof framing and plant room floor slabs
External walls	Cavity wall construction up to sill level. Outer skin of facing brickwork, inner skin of blockwork with rigid extruded polystyrene cavity insulation. Reconstructed stone to window sills and heads
Windows and doors	Sealed unit double glazing with clear glass in polyester powder-coated aluminium frames
Roof	Resin-bonded reconstituted slates on timber battens, insulation and timber trussed rafters. Polyester powder coated aluminium gutters and external downpipes
Stairs	Reception stairs precast concrete with screeded landings. Balustrades in coated tubular steel, hardwood handrails
Internal partitions	All partitions in concrete block
Ceiling	Suspended ceiling system comprising 600 × 600 mm mineral fibre ceiling tiles
Internal joinery	Hardwood veneer, flush-lipped solid core doors. Polished aluminium ironmongery. Hardwood skirtings, sill boards, door linings and architraves
Lifts	Electrically operated eight-person hydraulic lifts with stainless steel doors, surround and control panels
Sanitary fittings	White vitreous WCs and wash basins
Floor finishes	Medium-grade metal-faced full access flooring (250 mm overall floor zone) to office and corridor areas. Carpet finish high quality
Wall finishes	Plaster finishes or plasterboard drylining with joints taped and filled to general areas. One mist and two full coats of emulsion
Power	Wiring to and installing of three compartment floor boxes at a rate of 1 box/10 m2 net floor area and busbar power distribution system
Lighting	Based on 1994 CIBSE Guide for Offices at 450 lux at 0.75 musing 600 × 600 mm recessed modular fluorescent luminaries. The lighting scheme is based on open-plan offices
Heating	Gas-fired boiler in each plant room provides low pressure hot water for heating
Above-ground drainage	PVC soil vent waste pipework
Ventilation	Air-conditioning of office area using a VAV system with fresh air supplied via ducted system
WCs	A roof void mounted, packaged twin-fan extract unit
Hot and cold water services	Hot water to basins provided by central storage heaters, other hot and cold water services as suitable
Below-ground drainage	Flexible, jointed, vitrified clay or concrete pipework
External works	Includes access road, plot road and parking aisles. Concrete block paviours to all roads. Bitumen macadam to car bays. Footpath in concrete block paviours. Full landscaping. External irrigation system. External car park lighting

Detailed specification for 200,000 ft2 buildings
Foundations	Piled foundations and reinforced concrete ground beams, basement car park
Ground-floor slabs	Reinforced concrete floor slabs. Power floated finish
First, second and plant room floor slabs	Precast concrete planks with structural topping or insitu concrete on permanent formwork. First, second and plant room floor slabs give one-hour fire resistance
Structure	Internal steel frame, generally on a 6 and 7.5 × 6 m grid, supporting upper floors, roof framing and plant room floor slabs
External walls	Reconstructed stonework panels with aluminium-framed curtain-walling system
Windows and doors	Sealed unit double glazing with clear glass in polyester powder-coated aluminium frames
Roof	Flat roof construction comprising single-ply membrane on insulation
Stairs	Stairs precast concrete with screeded landings. Balustrades generally tubular stainless steel with hardwood handrails
Internal partitions	All partitions in concrete blockwork to core areas
Ceiling	Suspended ceiling system comprising 600 × 600 mm metal ceiling tiles
Internal joinery	Hardwood veneer, flush-lipped, solid core doors. Polished aluminium ironmongery. Hardwood skirtings, sill boards, door linings and architraves
Lifts	Glazed feature lifts to main entrance area. Electrically operated eight-person hydraulic lifts with stainless steel doors
Sanitary fittings	White vitreous WCs and hand basins
Floor finishes	Medium-grade metal-faced full access flooring (250 mm overall floor zone) to office and corridor areas. Carpet finish high quality. Reception areas to comprise high-quality ceramic tile finish
Wall finishes	Plaster finishes or plasterboard drylining with joints taped and filled to general areas. One mist and two full coats of emulsion
Power	Wiring to and installing of three compartment floor boxes at a rate of 1 box/10 m2 net floor area and busbar power distribution system
Lighting	Based on the 1994 CIBSE Guide for Offices at 450 lux at 0.75 m using 600 × 600 mm recessed modular fluorescent luminaries
Heating	Gas-fired boiler in each plant room provides low-pressure hot water for the heating
Above-ground drainage	PVC soil vent waste pipework
Ventilation	Air-conditioning of office area using a VAV system with fresh air supplied via ducted system
WCs	A roof void mounted, packaged twin-fan extract unit
Remaining specs as for 40,000 ft2 and 100,000 ft2 buildings