Shopping Centre Refurbishment - Cost model, October 1998 | Features

Indicative construction costs of shopping centre developments
Development type	Cost £/m2 gfa
Shopping centre, new build	new build
Shopping centre mall, comfort cooled	2200-3500
Shopping centre food court	2500-3600
Factory outlet centre mall - enclosed	2000-3000
Factory outlet centre mall - open	350-600
Retail shells, capped-off services only
-anchor store units	500-700
-medium/small store units	650-800
Landlord's back-up areas
-centre management/crèche	950-1450
-WCs	1400-1600
-enclosed, surface-level service yard	700-900
Shopping centre, refurbishment
Shopping centre mall, limited scope	700-1050
Shopping centre mall, comprehensive	1000-1500
Additional facilities, new build
Car parking, surface	35-50
Car parking, surface, landscaped	60-85
Car parking, grade and upoper level	120-180
Car parking, multistorey, flat slab	220-280
Car parking, semi-basement, naturally ventilated	290-340
Leisure shell	600-900
Multiplex cinema, shell only	600-850

Typical floor loadings
	kN/m2
Malls (pedestrian areas)	5.0-6.0
Malls (areas for maintenance access)	7.5
Retail sales area	5.0-6.0
Retail sales area (mezzanine)	4
Retail storage	5
Service yards	11
Plant	7.5
Car parking	2.5
Typical allowances for the dead load of partitions, suspended services, and ceilings and floor finishes in retail areas can range from 1.5 to 3.8 kN/m2

Cost breakdown
	Element cost (£)	Cost/m2 gfa (£)	% of total cost
Demolitions and alterations	38 000	8.84	0.94
Allowance for survey of existing structure		item @	£15 000
Demolishing existing roof structure; frame, slab and finishes; disposal		item @	£10 000
Demolishing existing rooflight glazing and secondary structure; disposal		230 m2 @	£10
Demolishing existing mall end panels; retaining structural steel framework		160 m2 @	£20
Removal of existing entrance screen		item @	£5,000
Removal of signs and other fixtures and fittings, including isolation of electrical supply		item @	£2,500
Frame	30 000	6.98	0.74
Structural steel frame for new rooflights; framing; fabrication		15 t @	£1,100
Surface finishes; intumescent paint, one-hour fire resistance; decorative top-coat		300 m2 @	£25
Allowance for additional structural repairs		item @	£6,000
Roof	576 800	134.14	14.2
Built-up felt roofing; cleaning and preparing substrate; replacement coverings		1600 m2 @	£27
Extra for upstands		360 m @	£24
Rooflight glazing; aluminium-framed, sealed double-glazed units		870 m2 @	£350
Extra for automatic smoke vents; including modifications to controls		870 m2 @	£170
Extra for secondary steelwork framing to main mall rooflight		270 m2 @	£30
Allowance for repair works to retained roof finishes and copings		Item @	£7,500
Rooflight access gantries; sliding action; support rails; 600 mm wide		32 m @	£1,000
Allowance for modifications to existing roof-level access platforms		Item @	£5,000
Allowance for latchway roof safety system		Item @	£20 000
External walls, windows and doors	98 400	22.88	2.42
Removal of existing, high-level, aluminium-framed, single-glazed windows		Item @	£1,500
Profiled grp infill panels to existing openings; contractor's design		225 m2 @	£135
Replacement windows; aluminium-framed sealed double-glazed units; 800 x 1350 mm; including grp cladding to reveals		9 nr @	£500
Allowance for modifications to bulkheads and surrounds to retained entrance doors and lobbies		Item @	£12 000
Allowance for replacement entrance screen, entrance doors and canopy		Item @	£50 000
Wall finishes	217 800	50.65	5.36
Removal of existing wall tiling		490 m2 @	£4
Strip-out of existing wall finishes; aluminium sandwich panels at high level; framing		500 m2 @	£11
Grp vertical linings; support framework; fixing to existing structure at high level; including trims etc		500 m2 @	£120
Grp gable-end linings; to interior of mall rooflights		150 m2 @	£300
Decorations; two coats emulsion paint		650 m2 @	£3
Wall tiling; resin-based conglomerate		765 m2 @	£125
Allowance for rubber-clad bump rails		24 m @	£195
Allowance for corner guards		190 m @	£16
Floor finishes	535 700	124.58	13.19
Breaking out existing wall tiling		4300 m2 @	£4
Making good existing screed; terazzo tiling; including trims, expansion joints, etc		4300 m2 @	£100
Extra for laying terazzo out of hours		4300 m2 @	£15
Allowance for doormats to entrance lobbies		Item @	£14 000
Extra for phased works maintaining access to shops		Item @	£10 000
Ceiling finishes	656 200	152.6	16.16
Strip-out of existing ceiling finishes; aluminium sandwich panels at high level; framing		1000 m2 @	£11
Strip-out of existing ceiling finishes; mineral fibre tiles; framing		2100 m2 @	£7
Cutting out isolated sections of existing grp suspended linings; making good		45 m2 @	£140
Grp suspended ceilings; support framework; fixing to existing roof structure at high level including trims, etc; forming holes for luminaires, sprinkler heads etc		3100 m2 @	£110
Extra over grp suspended ceilings for panels to match existing		32 m2 @	£165
Extra over grp suspended ceilings for concave profile ceiling panels		50 m2 @	£100
Extra over for access panels; generally		660 nr @	£95
Grp suspended beam casings; stainless steel bracket supports; secondary framework; fixing to existing structure; generally		525 m2 @	£190
Grp upstands, downstands and bulkheads; generally		626 m @	£65
Decorations; two coats emulsion paint at high level		4050 m2 @	£5
Fixed smoke curtains; glass, 500 mm to 1000 mm deep;		65 m @	£11
Cavity barriers; average height 450 mm; formed to profile of grp ceiling		115 m @	£35
Furniture and fittings	55 000	12.79	1.35
Allowance for mall furniture and fittings		Item @	£20 000
Allowance for banners in malls		Item @	£2,500
Allowance for signage and imaging		Item @	£30 000
Fire extinguishers		Item @	£2,500
Space heating and ventilation	235 500	54.77	5.8
Supply air installation; replacement of existing supply air grilles including modifications to ductwork		4300 m2 @	£15
Extract fan installation to low ceiling areas		Item @	£18 000
Allowance for localised mechanical smoke extract installation		Item @	£64 000
Temporary smoke extract installation		4300 m2 @	£10
Allowance for additional modifications to existing mechanical installations		Item @	£40 000
Testing and commissioning		Item @	£6,000
Electrical installations	510 500	118.72	12.57
Lighting installation to mall areas; including removal of existing lighting and luminaires		4300 m2 @	£90
Emergency lighting installation to malls; luminaires at high and low level		4300 m2 @	£5
Temporary mall lighting		4300 m2 @	£5
Small power installation to mall areas		4300 m2 @	£10
Allowance for power supply distribution to mechanical plant		Item @	£18 000
Allowance for additional modifications to existing electrical installations		Item @	£10 000
Testing and commissioning		Item @	£9,500
Gas installation	5 000	1.16	0.12
Relocation of existing gas pipework		Item @	£5,000
Protective installations	125 000	29.07	3.08
Remove existing hose reels and mains service, cap-off service, including removal of existing stone-clad hose reel plinths		6 nr @	£750
Modifications to existing sprinkler installations; new heads and distribution pipework; modifications to mains pipework, including decorations to pipework where exposed		4300 m2 @	£20
Extra for sprinkler installation to ceiling voids		Item @	£31 000
Testing and commissioning		Item @	£9,500
Communications installations	92 600	21.53	2.28
Fire alarm installation, fully addressable analogue type, including optical smoke detectors at high level in malls; public address system		4300 m2 @	£16
Temporary fire alarm installation		4300 m2 @	£5
Testing and commissioning		Item @	£2,300
Builders work in connection	50 000	11.63	1.23
Protection of existing systems		Item @	£2,000
Forming holes, chases, etc, allow 5%		Item @	£48 000
Preliminaries and contingencies	835 000	194.19	20.56
Contractor's overheads, site establishment and site supervision, allow 10%		Item @	£232 000
Extra for scaffolding and crash decks		Item @	£270 000
Design reserve and contingency, allow 7.5%		Item @	£242 000
Total construction cost (building only)	4 061 500	944.53	100

Shopping centre extension cost breakdown
	Element cost (£)	Cost/m2 gfa (£)	% of total cost
Demolitions	700 000	82.35	9.88
Demolition and site clearance, including temporary works		Item @	£450 000
Allowance for service diversions, drainage diversions, etc, including associated builders' work		Item @	£250 000
Substructure	960 000	112.94	13.54
Reinforced concrete ground beams and ground slab		5500 m2 @	£95
CFA piling, average diameter 500, disposal		5500 m2 @	£75
Allowance for pile testing		Item @	£25 000
Frame	739 500	87	10.44
Structural steel framing to shop units, 45 kg/m2		375 t @	£1,100
Extra for increased spans to large space users @ 70 kg/m2		120 t @	£1,100
Structural steel framing to mall roof canopy and mansards; hollow sections; allowance based on 30 kg/m2		25 t @	£1,800
Fire protection; vermiculite board; two-hour fire resistance		4500 m2 @	£30
Fire protection; intumescent paint; one-hour fire resistance; to mall roof canopy		600 m2 @	£25
Upper floors	186 900	21.99	2.64
Insitu concrete composite floor slabs; power floating		3300 m2 @	£50
Extra for 7.5 kN/m2 floor loading to plant room areas		300 m2 @	£5
Extra for forming knock-out panels for tenant's staircases		17 nr @	£1,200
Roof	1 251 900	147.28	17.67
Insitu concrete composite roof slab; retail shells		5650 m2 @	£48
Extra for forming knock out panels for tenant's roof access		17 nr @	£1,200
Roof coverings; single-ply membrane; insulation; ballast; perimeter treatments; retail shells		5720 m2 @	£45
Extra for upstands/flashings to roof openings		5720 m2 @	£45
Roof coverings; natural slates, battens, vapour barrier; insulation; forming mansard to high street frontage		400 m2 @	£70
Mall rooflights; sealed double-glazed units; powder-coated aluminium framing; secondary steelwork		530 m2 @	£350
Extra for perforated panel sunscreen; polyester coated mild steel sheet; tubular steel sub-frame		265 m2 @	£150
Extra for automatic smoke vents; interface to BMS and fire alarm		190 m @	£16
Allowance for external rooflight access installation		Item @	£75 000
Allowance for mansafe system to roof handrails to plan areas		Item @	£25 000
Allowance for rainwater goods		6250 m2 @	£5
Stairs	20 000	2.35	0.28
Insitu concrete stairs and half landing; overall rise 4.20 m; polyester-coated, mild steel handrails; finishes; plant room and roof access		2 nr @	£5,000
Allowance for access platforms and stairs within plantrooms		Item @	£10 000
External walls	256 000	30.12	3.61
Cavity wall; elevations to high street frontage; good quality facing brick, reconstituted stone features; cavity; insulation; 140 mm blockwork inner leaf		210 m2 @	£140
Cavity wall; rear elevations; facing bricks; cavity insulation; 140 mm blockwork inner leaf		1900 m2 @	£85
Louvre panels; powder-coated aluminium		210 m2 @	£250
Cladding; returns to mall entrance; composite aluminium insulated panels, framing; accessories		70 m2 @	£180
Windows and external doors	155 000	18.24	2.19
Windows to high street elevation; thermally broken aluminium frame; sealed double-glazed unit; polyester powder coating		30 m2 @	£300
Entrance screen; aluminium frame; sealed double-glazed units; polyester powder coating; 2 nr entrance door sets; ironmongery		90 m2 @	£500
Extra for double entrance door sets; complete		2 nr @	£5,000
Extra for cantilevered single-glazed planar entrance canopy; stainless steel supports		25 m2 @	£1,000
Steel faced; cellular core doors and frames; polyester powder coating; ironmongery		44 nr @	£1,500
Internal walls and partitions	259 800	30.56	3.67
Blockwork partitions; 140 mm average thick; divisions between retail units; fire stopping; head restraint		5300 m2 @	£40
Toilet cubicle partitions		10 nr @	£1,000
Melamine faced solid laminate access ducting		Item @	£15 000
Temporary shopfronts; painted ply		650 m2 @	£35
Internal doors	62 600	7.36	0.88
Flush doors; non-fire rated; solid core laminate faced; hardwood frames; decorations; stainless steel ironmongery; complete		14 nr @	£900
Fire shutters; to shopfronts of larger retail units only		50 m @	£1,000
Wall finishes	222 000	26.12	3.13
Grp wall linings; support framework; fixing to blockwork		950 m2 @	£120
Extra for profile services bulkhead/duct casing to mall perimeter; overall girth 1.2 m		150 m @	£180
Grp column cladding; forming profiled pilasters between retail units		65 m @	£350
Two coats emulsion paint to grp		1200 m2 @	£3
Facia panel over shopfront units; including shopfront fixing channel		120 m @	£350
Ceramic tiles; sand cement backing; to blockwork; to common areas		230 m2 @	£55
Floor finishes	103 100	12.13	1.45
Terrazzo tiles; sand cement screed; average 50 mm thick; including allowance for skirting		600 m2 @	£80
Extra for inlaid patterns and features		600 m2 @	£30
Extra for angle trims, divisions strips and movement joints		600 m2 @	£20
Ceramic tiles; sand cement screed; average 50 mm thick; including coved skirtings		60 m2 @	£60
Concrete hardener/dust seal; to plant rooms		300 m2 @	£5
Mats and matwells		50 m2 @	£400
Ceiling finshes	48 400	5.69	0.68
Grp suspended ceilings and linings; support framework; fixing to soffit of roof structure at high level; including trims, etc		450 m2 @	£100
Suspended ceilings; metal pan tiles; lay in grid; generally		60 m2 @	£40
Decorations; two coats emulsion paint at high level		250 m2 @	£4
Furniture and fittings	150 000	17.65	2.12
Allowance for mall furniture		Item @	£20 000
Centre directory boards		2 nr @	£5,000
Vanity units; mirrors; fittings, etc to WCs		Item @	£10 000
Statutory and directional signing to mall		Item @	£30 000
Allowance for banners and high-level features		Item @	£10 000
Allowance for features and planting		Item @	£50 000
Guard rails and barriers to service areas		Item @	£20 000
Sanitary fittings	10 700	1.26	0.15
WCs, urinals, washhand basins; generally		33 nr @	£300
Extra for fittings for disable WCs		1 nr @	£100
Cleaners sinks		2 nr @	£350
Disposal installations	60 900	7.16	0.86
Rainwater disposal; cast-iron downpipes and fittings		8500 m2 @	£3
Waste, soil and vent installation; cast-iron pipework and fittings		33 nr @	£300
Capped connection; soil stack; cast-iron pipework and fittings; to retail shells		17 nr @	£1,500
Water installations	40 800	4.8	0.58
Hot and cold water service; calorifiers; hot and cold water storage; distribution to WCs etc		51 nr @	£300
Capped connection; flow meter to retail shells		17 nr @	£1,500
Space heating and air treatment	247 800	29.15	3.5
Supply and extract ventilation to mall; low-temperature, hot-water heating including heat source; chilled water, air handling units; perimeter ductwork distribution; high-quality diffusers; including provision for smoke extract through air-handling units		660 m2 @	£330
Warm air curtains; to mall entrance		Item @	£15 000
Extra for toilet extract installation		Item @	£10 000
Plant room ventilation		Item @	£5,000
Electrical installations	211 100	24.84	2.98
Mains and sub-mains installation		Item @	£100 000
Landlord's small power distribution in mall and common areas		660 m2 @	£32
Lighting and luminaires to mall		600 m2 @	£90
Lighting and luminaires to common areas		60 m2 @	£40
Extra over for emergency lighting installation		660 m2 @	£10
Electrical services to retail shells		17 nr @	£1,000
Power to mechanical services		Item @	£10 000
Gas installation	60 500	7.12	0.85
Gas installation		Item @	£10 000
Capped off gas supplies to retail shells; check metering		17 nr @	£1,500
Lift installations	25 000	2.94	0.35
Dock levellers to large store units		5 nr @	£5,000
Protective installations	89 700	10.55	1.27
Sprinkler installation; mall only		660 m2 @	£20
Extra for capped-off supply to shop units including water storage		17 nr @	£3,000
Lighting protection		8500 m2 @	£2
Earthing and bonding		8500 m2 @	£1
Communications installations	90 100	10.6	1.27
Fire, smoke detection and alarm system; analogue addressable type; to mall and public areas; including allowance for capacity for retail units in control panel; interface with management centre		Item @	£25 000
Extra for temporary automatic fire detection in retail shells		17 nr @	£300
Public address system; mall and common areas only		Item @	£10 000
Intruder detection; monitoring to entraces to malls and retail shells		8500 m2 @	£2
Access control		Item @	£5,000
CCTV system; 10 nr cameras		Item @	£25 000
Wireways for landlord's telephones and data		Item @	£3,000
Special installations	60 000	7.06	0.85
Building management system; mall and common areas; interface with retail units		Item @	£60 000
Builder's work in connection	45 000	5.29	0.63
Forming holes, chases, etc - allow 5%		Item @	£45 000
Preliminaries and contingencies	1 030 000	121.18	14.53
Contractor's overheads, site establishment and site supervision, excluding design fees - allow 12%		Item @	£727 000
Contingency sum - allow 5%		Item @	£303 000
Total construction cost (building only)	7 086 800	833.73	100

Regional variations
All costs in this article are based on schemes in the South-east and should be adjusted by the following location factors fo projects in other areas
Inner London	1.1
Outer London	1.04
South-west	0.95
East Midlands	0.93
West Midlands	0.95
East Anglia	0.95
Yorkshire and Humberside	0.93
North-west	0.98
Northern	0.93
Scotland	0.96
Wales	0.94
Northern Ireland	0.82