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Keep up to dateIndicative cost of refurbishment | |
Typical cost (£/m2 GIFA) | |
Minor refurbishment | 215-700 |
Medium refurbishment | 700-1050 |
Major refurbishment | 1050-1600+ |
Costs are at second quarter 2004 price levels based on a central London location. The cost levels include for completion of office space to category A fit-out, but exclude external works |
Opportunities and constraints | ||
Securing best value out of a refurbishment project involves a careful balance between making the best use of a building’s potential while minimising the costs and time penalties that might be necessary to work around a building’s constraints. | ||
The advantages and disadvantages of major elements of office refurbishment are summarised in this table: | ||
Opportunities | Constraints | |
Planning | ||
Existing building | 1 Leases | |
2 Location | ||
3 Character | ||
Structure | 1 Structural system | |
2 Structural grid | ||
3 Live and dead loads | ||
4 Floor to ceiling heights | ||
internal environment | 1 Floor plate | |
redesigning common areas to improve circulation between wings design cores to facilitate sub-division of floor plates | ||
2 Design features | ||
generous reception areas with a limited number of good quality design features lifts – size, quality of ride and finish WCs and other common areas | ||
3 Envelope performance | ||
4 Increasing the productivity of office space | ||
Indicative costs of office building services options for refurbishment | |||
Shell and core | Fit-out | Fit-out | |
Space heating and air treatment £/m2 (GIFA) | On-floor services £/m2 (NIFA) | Extra for floors and ceilings £/m2 (NIFA) | |
4 pipe fan coil unit | 95-115 | 160-200 | 75-85 |
Displacement ventilation with cooling at the AHU and LTHW perimeter heating | 105-130 | 115-145 | 50-60 |
Chilled ceiling with perimeter chilled beams and LTHW perimeter heating | 95-115 | 225-270 | 35-45 |
Passive multi-service beams with LTHW perimeter heating | 95-115 | 230-275 | 50-60 |
Active multi-service beams with LTHW perimeter heating | 95-115 | 260-285 | 50-60 |
Shell and core costs include landlord’s plant and distribution only. Fit-out costs include on-floor mechanical services, luminaires and lighting control, power to on-floor services and lighting, fire alarms and controls only. Small power, builder’s work and preliminaries are excluded. Costs are at 2nd quarter 2004 levels, based on a central London location. |
Location factors | |
Inner London | 1.00 |
Outer London | 0.94 |
South-east | 0.89 |
South-west | 0.81 |
East Midlands | 0.81 |
West Midlands | 0.81 |
East Anglia | 0.85 |
Yorkshire & Humberside | 0.78 |
North West | 0.81 |
Northern | 0.80 |
Scotland | 0.81 |
Wales | 0.80 |
Northern Ireland | 0.68 |
Datafile | |||
element cost | cost/m2 gfa £ | % of total cost | |
Strip-out | 111,000 | 25.23 | 2.05 |
Strip-out of existing fit-out; plasterboard ceiling, timber floor, partitions and services 3,700 m2 @ 30 | |||
Demolitions and alterations | 208,000 | 47.27 | 3.85 |
Demolition and removal of existing core, incorporating concrete stair, central lift shaft and core walls Item @ 50,000 | |||
Demolition and removal of existing roof slab, lift motor room and dormers plan area of existing roof) 470 m2 @ 100 | |||
Demolitions and alterations generally; removal of existing windows to rear lightwell, cutting to enlarge existing openings, filling openings, removing concrete casings to existing steel beams, removal of internal walls, breaking out isolated areas of ground floor slab 3,700 m2 @ 30 | |||
Substructure | 118,300 | 26.89 | 2.19 |
Forming foundation to new core and lightwell extension; pad foundations, ground beams, ground slab, site excavation, disposal; all works within existing lightwell (area based on footprint of core and lightwell) 140 m2 @ 450 | |||
New drainage works to core and lightwell extension, adaptions to existing connections and making good 140 m2 @ 90 | |||
Alterations to lightning protection, waterproof earthpots, including breaking through existing basement slab 610 m2 @ 25 | |||
Waterproofing works to isolated areas of existing basement 610 m2 @ 45 | |||
Frame and upper floors | 445,600 | 101.27 | 8.25 |
General adaptation and making good to existing steel frame; works in isolated areas; recasing etc 3,700 m2 @ 20 | |||
Steel frame to new core extension; fabrication, erection, intumescent paint finish (based on 540m2 @ 80 kg/m2) 43 t @ 3,500 | |||
225 thick reinforced concrete slab on holorib decking 540 m2 @ 90 | |||
Feature steelwork supporting lightwell curtain walling; exposed CHS; intumescent paint finish Item @ 50,000 | |||
Steel frame to new flat roof slab; forming padstones; fabrication; erection; intumescent paint finish (based on 460m2 @ 60 kg/m2) 28 t @ 2,500 | |||
Steelwork and secondary steelwork; pitched to form new mansard roof; adaptions to existing frame; making good; intumescent paint finish (based on 145m2 @ 100kg/m2 – based on plan area of mansard) 15 t @ 3,500 | |||
Roof | 236,000 | 53.64 | 4.37 |
New roof slab; 130 thick reinforced concrete slab on holorib decking 480 m2 @ 80 | |||
Single ply roof membrane; insulation, vapour barrier and walkway tiles 480 m2 @ 90 | |||
Allowance for junctions of roof membrane with existing work; flashings, aprons, upstands, edge trims, fall junctions, cover strips 480 m2 @ 50 | |||
Allowance for repairs, alterations and making good to retained roof features, parapets etc 480 m2 @ 30 | |||
Mansard roof construction, comprising bespoke sawn softwood framing to mansard and dormer openings, plywood boarding, insulation and vapour barriers; felt and natural slate coverings; lead cladding to dormers with lead aprons (quantity based on plan area of the mansard roof) 145 m2 @ 615 | |||
Pitched screen to open roof level plant enclosure; steel frame with lead-clad timber panels 60 m2 @ 195 | |||
Additional works at roof level; plant supports, plinths and upstands, safety balustrade; new drainage and repairs to existing 420 m2 @ 36 | |||
Stairs | 212,000 | 48.18 | 3.92 |
Feature staircase; steel frame, landings and treads with aluminium nosings, structural glazed balustrades to landings with stainless steel balustrade/handrails 7 flights @ 22,000 | |||
Fire escape stair from ground to fifth floor; steel with concrete infill treads; half landings; painted mild steel handrails and balustrades 6 flights @ 6,000 | |||
Precast concrete staircase from basement to ground and ground to first floor including mild steel balustrade 2 flights @ 10,000 | |||
Allowance for handrails to access ramp in reception Item @ 2,000 | |||
External walls, windows and doors | 528,100 | 120.02 | 9.77 |
Cleaning surfaces of existing stone facade; fine water spray and brush 850 m2 @ 50 | |||
Allowance for stone repairs to existing facade Item @ 10,000 | |||
New Portland Stone cladding to ground floor entrances; hand set; to match existing Item @ 50,000 | |||
Glazed entrance screen 5 m high overall including central revolving entrance door and 2 side entrance doors Item @ 60,000 | |||
Blockwork, insulation and self-coloured render to escape stair flank wall 250 m2 @ 135 | |||
Curtain wall to lightwell; double-glazed units in stick system; secondary framing; installed within confined conditions of existing lightwell 130 m2 @ 700 | |||
Rainscreen cladding; secondary framing; installed within confined conditions of existing lightwell 110 m2 @ 350 | |||
Louvre plant screen; polyester powder coated; steel frame 95 m2 @ 270 | |||
Allowance for repairs and redecorations to existing windows (60 ) Item @ 50,000 | |||
Full height double glazing to new dormers; including sliding doors; ironmongery 112 m2 @ 650 | |||
Aluminium framed single-glazed secondary windows 160 m2 @ 190 | |||
Full height windows to replace existing including enlarging existing opening 4 @ 4,000 | |||
Escape doors; purpose-made timber; 1100 x 3000 high; ironmongery 3 @ 2,500 | |||
Internal walls and partitions | 126,700 | 28.80 | 2.35 |
140 blockwork to basement plant areas and cores 1,800 m2 @ 40 | |||
Metal stud partitions; 170 thick 300 m2 @ 70 | |||
Duct panelling behind WCs 20 @ 450 | |||
Glazed lift enclosure at ground floor reception; 3 m high 40 m2 @ 550 | |||
Plasterboard linings to existing columns including framework; 3.60 m high, 1.00 m girth 15 @ 180 | |||
Internal doors | 97,200 | 22.09 | 1.80 |
Single door to plant rooms including frame and ironmongery 5 @ 1,300 | |||
Single doors to landlord’s areas 4 @ 900 | |||
Solid core single leaf doors to core entrances; fire rated; full height; glazed vision panels; stainless steel ironmongery; hardwood frames and architraves; clear stain finish to hardwood; veneer finish to door leaf 12 @ 1,400 | |||
Ditto; non-fire rated to WCs and cleaners’ cupboards 25 @ 1,200 | |||
Single riser access doors to office and core areas; fire rated; hardwood frames and architraves; clear stain finish to hardwood; veneer finish to door leaf 25 @ 1,100 | |||
Ditto; double doors 8 @ 1,600 | |||
Wall finishes | 152,300 | 34.61 | 2.82 |
Plasterboard linings to existing walls; fixed direct to substrate 1,100 m2 @ 25 | |||
Vinyl matt emulsion paint to plasterboard 4,000 m2 @ 3 | |||
Waterproof render to isolated existing areas in basement walls 650 m2 @ 40 | |||
Natural stone tiling to WCs 260 m2 @ 180 | |||
Feature Portland stone walls to reception 100 m2 @ 400 | |||
Floor finishes | 228,800 | 52.00 | 4.23 |
Natural stone to reception and lobby areas 300 m2 @ 250 | |||
Natural stone to WCs 50 m2 @ 180 | |||
Raised floor; 300 cavity; including cutting holes for diffusers 2,430 m2 @ 40 | |||
Extra over raised floors for; mechanically fixing pedestals to existing slab; dust-sealing plenum 2,430 m2 @ 10 | |||
Rubber floor to escape stair 160 m2 @ 43 | |||
Galvanised steel walkways within risers 80 m2 @ 130 | |||
Skirtings, surface fixed, painted MDF 600 m @ 10 | |||
Ceiling finishes | 176,000 | 40.00 | 3.26 |
Painted plasterboard on battens to office areas, lobbies and WCs; including bulkheads, trims and apertures for linear downlighters 3,100 m2 @ 50 | |||
Allowance for feature ceiling to reception 140 m2 @ 150 | |||
Furniture and fittings | 62,600 | 14.23 | 1.16 |
Allowance for reception area fittings; reception desk; mailboxes, signage, mats and matwells Item @ 35,000 | |||
Blinds fixed to external side of secondary glazing, and dormer windows (measured elsewhere) 290 m2 @ 40 | |||
Fittings to WCs including feature stone trough hand basin; mirror finish vanity wall unit; fittings 20 @ 800 | |||
Sanitary fittings | 20,000 | 4.55 | 0.37 |
WC sanitary fittings; WCs, taps, waste and trap; basins included in fittings and furniture 20 @ 800 | |||
Allowance for cleaners sinks 10 @ 400 | |||
Disposal installations | 53,400 | 12.14 | 0.99 |
Allowance for rainwater disposal; downpipes and connections to below ground drainage 4,400 m2 @ 4 | |||
Allowance for soil, waste, drains and overflow installations; replacement soil stacks in new risers; connections to below ground drainage 4,400 m2 @ 7 | |||
Allowance for pumped drainage from basement areas Item @ 5,000 | |||
Water installations | 36,800 | 8.36 | 0.68 |
Mains water services, comprising sectional storage tank, booster pump set, pipework, valves, insulation and water treatment 4,400 m2 @ 5 | |||
Hot water services by local water storage heaters 6 @ 800 | |||
Water service provision for floor vending/kitchenettes; capped off @ 2,000 | |||
Space heating and ventilation | 502,100 | 114.11 | 9.29 |
Replacement heat source and distribution; gas-fired boiler plant, LTHW primary and secondary pumpsets, pressurisation units and pipework within plantroom Item @ 75,000 | |||
Replacement LTHW heating to stairs, toilets and circulation areas 670 m2 @ 16 | |||
Supplementary LTHW heating to lightwell glazing Item @ 10,000 | |||
Low level displacement ventilation system; roof-level air handling and chiller plant; chilled water distribution at roof level only; office supply and extract distribution ductwork; supply air diffusers 4,400 m2 @ 70 | |||
Supply air diffusers to office areas only 2,430 m2 @ 10 | |||
Package air-conditioning system to entrance lobby and reception area Item @ 10,000 | |||
LTHW radiator system to general office floor area 1,730 m2 @ 20 | |||
Replacement trench heating installation to upper level office floors with dormer windows 700 m2 @ 25 | |||
Toilet extract system Item @ 12,000 | |||
Electrical installations | 360,400 | 81.91 | 6.67 |
Replacement mains switchgear, cabling, containment and landlord’s distribution boards 4,400 m2 @ 20 | |||
Small power; landlord’s areas only 4,400 m2 @ 6 | |||
Power supply to mechanical services 4,400 m2 @ 5 | |||
Lighting installation to landlord’s areas, including emergency lighting 670 m2 @ 30 | |||
Lighting installation to office areas including lighting control 2,430 m2 @ 50 | |||
Emergency lighting to office areas 2,430 m2 @ 20 | |||
Feature lighting to entrances Item @ 25,000 | |||
Earthing and bonding 4,400 m2 @ 2 | |||
Lift installation | 180,000 | 40.91 | 3.33 |
Lift installation; 10 person fire fighting lifts serving 7 storeys 2 @ 90,000 | |||
Gas installations | 8,800 | 2.00 | 0.16 |
Gas service to boilers only from gas meter 4,400 m2 @ 2 | |||
Protective installations | 18,800 | 4.27 | 0.35 |
Allowance for dry riser inlets Item @ 10,000 | |||
Lightning protection 4,400 m2 @ 2 | |||
Communications installations | 119,000 | 27.05 | 2.20 |
Addressible fire alarm system; panel, detectors, sounders 4,400 m2 @ 8 | |||
Extra for detectors and sounders in office areas 2,430 m2 @ 5 | |||
Allowance for telephone and data containment only 4,400 m2 @ 4 | |||
Security system; allowance for intruder detection including door and window security contacts at low level 4,400 m2 @ 10 | |||
CCTV monitoring; landlord’s areas only Item @ 10,000 | |||
Special installations | 154,000 | 35.00 | 2.85 |
Building management system comprising motor control centres, isolators, starters and all controls 4,400 m2 @ 35 | |||
Builder’s work in connection | 100,000 | 22.73 | 1.85 |
Forming holes and chases; firestopping Item @ 100,000 | |||
Preliminaries and contingencies | 1,148,000 | 260.91 | 21.24 |
Testing and commissioning of building services installations | |||
Allow 5% of services cost | |||
Item @ 78,000 | |||
Contractor’s overheads, site establishment and site supervision, excluding design fees | |||
Allow 16% | |||
Item @ 693,000 | |||
Design reserve and contingency | |||
Allow 7.5% | |||
Item @ 377,000 | |||
Total construction cost of office refurbishment | 5,403,900 | 1,228.17 | 100.00 |