ºÚ¶´ÉçÇø

Read our policy.

Close menu
Classroom extension cost breakdown
Ìýelement costcost/m2 gfa £% of total cost
Substructure36,100116.459.12
Excavation and disposal 140 m2 @ 30ÌýÌýÌý
Concrete strip foundations, masonry work below DPC; blockwork and facing brickwork 90 m @ 130 ÌýÌýÌý
Reinforced insitu concrete foundations and ground slab, including service trench; vapour barrier; hardcore, excavation and disposal 310 m2 @ 65ÌýÌýÌý
Roof50,200161.9412.68
Softwood roof trusses 380 m2 @ 35ÌýÌýÌý
Board insulation to roof 310 m2 @ 15ÌýÌýÌý
Cement slate roofing including all eaves, ridge tiles and labours; measured on plan 380 m2 @ 60ÌýÌýÌý
Aluminium rainwater down pipes 40 m @ 75ÌýÌýÌý
Aluminium gutters 90 m @ 65ÌýÌýÌý
Fire barriers 40 m @ 15ÌýÌýÌý
External walls30,80099.357.78
Brick cavity wall, facing brick outer skin with cavity, 140mm inner blockwork leaf 220 m2 @ 140 ÌýÌýÌý
Windows and external doors29,10093.877.35
Proprietary aluminium framed, double glazed windows, doors and solid aluminium faced panels; powder coated finish 55 m2 @ 350ÌýÌýÌý
Double door steel security doors, including all ironmongery 1 @ 1,600ÌýÌýÌý
Double door aluminium framed glazed doors and screens to paved areas, including all ironmongery 15 m2 @ 550ÌýÌýÌý
Internal walls and partitions 12,20039.353.08
Partitions; 100/140 blockwork (average rate) 285 m2 @ 35ÌýÌýÌý
WC cubicle partitions; laminated plastics, including all ironmongery 4 @ 550ÌýÌýÌý
Internal doors9,70031.292.45
Internal fire doors, georgian wired glass vision panel, stainless steel ironmongery to classrooms 5 @ 900ÌýÌýÌý
Double fire door, georgian wired glass, stainless steel ironmongery to corridor 1 @ 1,100ÌýÌýÌý
Wrot softwood storage cupboard door, stainless steel ironmongery 5 @ 450ÌýÌýÌý
Non fire-rated doors, stainless steel ironmongery to WC 3 @ 600ÌýÌýÌý
Wall finishes13,20042.583.33
Plaster and one mist coat, three coats of emulsion paint 760 m2 @ 15ÌýÌýÌý
Ceramic wall tiles, full height in toilets and selected classroom areas 40 m2 @ 45ÌýÌýÌý
Floor finishes14,40046.453.64
Screed cement screed 310 m2 @ 15ÌýÌýÌý
Carpet tiles 150 m2 @ 25ÌýÌýÌý
Safety vinyl to WC areas and practical areas, including skirtings 90 m2 @ 30ÌýÌýÌý
Heavy duty vinyl to circulation areas, including skirtings 68 m2 @ 40ÌýÌýÌý
Entrance matting with aluminium matwell 2 m2 @ 275ÌýÌýÌý
Furniture and fittings19,50062.94.92
Storage trays containers 3 @ 2,500ÌýÌýÌý
Storage units – allowance of one double cupboard per classroom 3 @ 500ÌýÌýÌý
Worktops, including cut out for sink, 3000x600 3 @ 125ÌýÌýÌý
Coat hooks, fixed to masonry 100 @ 25ÌýÌýÌý
Pinboards, 1000 × 2000 6 @ 75ÌýÌýÌý
Pinboards, 1000 × 1200 2 @ 50ÌýÌýÌý
Whiteboards: Interactive 3 @ 1,500ÌýÌýÌý
Whiteboards: Magnetic 3 @ 100ÌýÌýÌý
Signage 1 @ 2,000ÌýÌýÌý
Mirrors 640 × 460 7 @ 40ÌýÌýÌý
Sanitary fittings5,10016.451.29
WCs 6 @ 210 ÌýÌýÌý
Urinals, including side panel 2 @ 220 ÌýÌýÌý
Hand basins 8 @ 180 ÌýÌýÌý
Disabled toilet, including WC, wash hand basin, grab rails and other fittings 1 @ 700 ÌýÌýÌý
Single stainless steel sinks to classrooms, 1200 × 600 3 @ 200 ÌýÌýÌý
Cleaners sink, 510 × 380 1 @ 700ÌýÌýÌý
Disposal installations6,200201.57
Waste, soil and vent installation; PVCu pipework and fittings 310 m2 @ 20ÌýÌýÌý
Water installations9,20029.682.32
Cold water points 21 @ 250ÌýÌýÌý
Hot water points 13 @ 300ÌýÌýÌý
Space heating and air treatment37,2001209.39
Space heating, all costs associated with the supply and installation of the heating system, temperature control and distribution pipework 310 m2 @ 120 ÌýÌýÌý
Ventilation installations5,00016.131.26
Ventilation extraction to WC areas Item @ 5,000ÌýÌýÌý
Electrical installations31,0001007.83
Mains and sub-mains installation 310 m2 @ 20ÌýÌýÌý
Small power installation 310 m2 @ 30 ÌýÌýÌý
Lighting and general luminaires; emergency lighting 310 m2 @ 50 ÌýÌýÌý
Gas installation1,6005.160.41
Gas Installations, all costs associated with the supply and installation of gas 310 m2 @ 5ÌýÌýÌý
Protective installations1,0003.230.25
Lightning protection, earthing and bonding 1 Item @ 1,000ÌýÌýÌý
Communications installation12,20039.353.08
Fire alarm installation; smoke detectors; call points Item @ 4,000ÌýÌýÌý
Telephone and data wireways; internal telephone system Item @ 2,200ÌýÌýÌý
Security installation; intruder detection, CCTV to existing control unit etc 1 Item @ 6,000ÌýÌýÌý
Builder's work in connection5,40017.421.36
Forming holes, chases etc, allow 5% Item @ 5,400 ÌýÌýÌý
Preliminaries and contingencies60,400194.8415.25
Preliminaries, allow 15% Item 50,300ÌýÌýÌý
Contingency sum, allow 3 % Item 10,100ÌýÌýÌý
Total construction cost – building only396,0001,277.41100
Ìý
Alternative design options
Extra over cost/saving inclusive of preliminaries and contingencies (£/m2) GIFA
Option 1: Replace a blockwork inner wall with a sliding folding partition, including building in steel beam 30
Option 2: Dedicated ICT suite in small room, cost of benching not included 18.5
Option 3: Replace brick cavity walling with timber rainscreen cladding 37.5
Option 4: Replace brickwork cavity wall with a render finish on blockwork cavity external wall –10.50
Option 5: Replace pitched cement tiles with Decra metal roof tiles 14
Option 6: Replace pitched cement tile roofing with single ply membrane –10.00
Option 7: Replace cement tile roofing with a green roof system–75.00
Option 8: Replace all internal blockwork partitions with acoustic metal stud partitions 5.5
Option 9: Replace 50% of the plaster and paint to blockwork walls with hygienic plastic sheeting 58