Prefabrication of services | Archive Titles

Model 1 cost comparison for packaged roof-mounted plant room
Packaged plant room versus conventional site construction/installation
	Prefabricated (£)	Conventional (£)
Enclosure (8·6 m x 11 m x 3·7 m) Includes separate chiller enclosure and lift motor room	67 500	45 000
Heating Plant 3 x 200 kW boilers; primary/secondary pumps; pressurisation unit etc	41 500	41 500
Heating system pipework; insulation and ancillaries	48 000	57 700
Chiller plant 1 x 562 kW chiller; primary/secondary pumps pressurisation unit; external condenser	106 000	106 000
Chilled water system pipework, insulation and ancillaries	38 000	44 900
Part of ahu; 10m3/s, thermal wheel, heating and cooling coils, extract fan only	20 300	20 300
Gas installation	4500	5300
Cranage	18 500	by main contractor
Total	£344 300	£320 700

Model 2 . Cost comparison for a ptre-assembled 560 kw boiler system
Conventional site installation versus preassembled boiler system mounted on skid
	Preassembled (£)	Conventional (£)
Delivery/offloading/positioning	800	400
Site labour	–	3500
Materials (pipework, wiring, controls, insulation)	Inc in equipment	7500
Plant and equipment	29 900	20 100
Supervision	400	1600
Plant hire	200	800
Testing and commissioning (boilers, pressurisation unit, water balancing and controls)	1100	2300
Total	£32 400	£36 200

Model 3. Cost comparison for multi-service prefabricated module for four-pipe fan coil system
Multi service versus conventional site installation
	Prefabricated (£)	Conventional (£)
Fabrication and delivery to site of Multi-service modules (comprising busbar bracketry, ductwork and pipework)	37 700	N/A
Heating and chilled water pipework	Inc above	13 400
Primary ductwork (manufactured and delivered to fabricator)	29 100	29 100
Busbar/basket tray (busbar brackets delivered to fabricator, busbar and basket tray delivered to site for installation onto modules)	7300	7300
On site labour	12 500	52 200
Access equipment	1000	2300
Total	£87 600	£104 300
Note: works are for shell and core, and category A fit-out; insulation to services not included in either option.
The following exclusions relate to the cost models: inflation beyond fourth quarter 2001; incoming statutory services; builder’s work in connection with services; main contractor’s overheads, profit and attendance; main contract preliminaries; professional and prescribed fees; contingencies and design reserve; tax allowances; vat.