Welcome to building.co.uk. This site uses cookies. Read our policy.

Engineering services design parameters
Cooling load 125 W/m2
Heating load 90W/m2
Fresh air requirement 12 l/s per person
Occupational density 1 person per 10 m2 of net lettable area
Air-conditioning terminal unit density: perimeter zone 1/27 m2 (6x4.5 m module)
Air-conditioning terminal unit density: internal zone 1/50 - 80 m2
Internal design temperature 22 degrees C (summer); 21 degrees (winter)
External design temperature 28 degrees C (summer); -4 degrees (winter)
 
Capital costs for the four systems
VAV (£) VRF (£) fan-coil units (£) chilled ceilings (£)
Air conditioning systems 1 482 000 1 079 000 1 190 000 1 489 000
Electrical work in connection 47 000 36 000 42 000 16 000
Builder's work in connection 107 000 59 000 59 000 74 000
Preliminaries, overheads and profit and attendance 286 000 205 000 226 000 276 000
Allocation of design fees 231 000 166 000 182 000 223 00
Sub-total 2 153 000 1 545 000 1 699 000 2 078 000
Capital allowances relief (NPV) (559 000) (401 000) (441 000) (540 000)
Total capital cost 1 594 000 1 144 000 1 258 000 1 538 000
 
Life expectancy for components of the four systems (years)
Item VAV VRF fan-coil units chilled ceilings
Central cooling plant 15-20 Aug-15 15-20 15-20
Central boiler plant 15-25 n/a 15-25 15-25
Pumps 15-20 n/a 15-20 15-20
Air-handling units 15-20 15-20 15-20 15-20
Indoor terminal units 15-20 Aug-15 15-20 n/a
Chilled ceiling elements n/a n/a n/a 25-30
Chilled beams n/a n/a n/a 25-30
Radiant panels n/a n/a n/a 25-30
Flexible hoses 10 10 10 10
Controls actuators Oct-15 Oct-15 Oct-15 Oct-15