BCIS - A Worked Example
BCIS - A Worked Example
3.1 The spreadsheets used
The worked example is illustrated here with printouts from the spreadsheets used to carry out all the tedious arithmetic. Once again, it has to be emphasised that these spreadsheets make no decisions for the quantity surveyor. At best they only relieve the quantity surveyor of some of the boredom but still require the quantity surveyor to make judgements about the accuracy of the figures input on the spreadsheets and the results that they show. One of the principal features of any good software is the building in of checking procedures which automatically throw up any errors in input of data and perhaps anomalous results. Such checks are present in the spreadsheets where appropriate. Building in these checks has to be undertaken with care and is best left to the minimum appropriate. Too many and the user can be lulled into a false sense of security and may even cause errors themselves e.g. by being too restrictive when an input outwith the criteria could be perfectly legitimate – just not thought of when the software was designed. (Remember the fuss about the year 2000 and computer programs not able to cope? This was caused by software written to cope only with dates in the range 01 to 99 and in one century.)
The data used in the exercise comes from the BCIS files with kind permission of the RICS.
3.1.1 The client and the brief
Before the quantity surveyor can do a cost plan he needs a client who needs a building who needs advice! So here is the client’s brief as agreed at feasibility stage:
The client is a local health board, which wishes to procure a health centre on the outskirts of a major city. For this example we have used Edinburgh, the capital of Scotland, UK.
The centre must be capable of accommodating between four and six general practitioners (GPs), two practice nurses, a chiropodist and have two treatment rooms, patient waiting area, reception, offices, dispensary, private and public toilets. It should include all up-to-date provisions for disabled patients.
Security will feature highly on the list of services provided with panic alarms in all staff areas, CCTV in all public areas and circulation areas, an intruder alarm system and a fire alarm system together with a sprinkler system. In all a GFA of around 800–900 m2 over two storeys is envisaged. The building is to be built in masonry with solid concrete ground floor, a pitched roof with a profiled metal covering and edge trims.
So, now that we have that brief, the quantity surveyor can look up the database and find what data is being held on health centres. These can be found in Section 421 of the BCIS: Health centres, clinics, group practice surgeries. Whether access is by paper copy or by computer, the reference 421 always applies to this building type.
The quantity surveyor will search through the analyses listed and photocopy or download the analyses which seem to be most appropriate. From there, the spreadsheets are used as follows:
The first spreadsheet, ‘Analysis1’, is used to gather some basic data, bring costs to current costs and allow that data to be sorted into increasing or decreasing levels of cost. From that data the quantity surveyor can choose a cost per m2 of GFA which can be used for the proposed building. It may also be possible to choose just one analysis, which is very close to the proposal; it may not! The quantity surveyor’s task is very much easier if the former is the case but there are ways to deal with the corollary.
The second spreadsheet, ‘Analysis2’, is used to help the quantity surveyor determine what the distribution of cost across the elements should be. To do this, the spreadsheet has all the cost data (from two or three of the analyses already listed on the previous spreadsheet) input and the individual cost of each element is then expressed as a percentage of the total tender cost less contingencies.
The third spreadsheet, ‘Analysis3’, is used to prepare the cost plan and calculate the realistic first estimate. Once the client and the other members of the design team have agreed that first estimate, the die are cast; there is no going back; recall what was said earlier about egg on faces – particularly quantity surveyors’ faces etc.
The percentage breakdowns from the second spreadsheet are also incorporated here and assist the quantity surveyor in making the allocation of the total cost across the elements and sub-elements. This spreadsheet includes for the first time percentage allowances for Price and Design Risk and Contingencies. Note that these are in addition to the bare total of element cost and Preliminary works.
Note that all the spreadsheets incorporate a ‘contract name’ and a ‘contract reference’. Note also that a date has to be given on every piece of paper printed out and that a time is also included. The latter may seem like just a little too much detail, however, consider that with a spreadsheet, the calculation work is a press of a button away then it can be seen that the quantity surveyor could produce several versions of the cost plan in a single day. Indeed this is done using one of the great features of the spreadsheet ‘What if?’ Not all of the spreadsheets need be saved for posterity, but several ‘What ifs?’ can be made up and even presented to the client/design team meeting for approval.
The remaining two spreadsheets will be discussed a little later when we move to the detail design stage and the cost checking which follows.
When you start work on the spreadsheets from the CD, you will notice that the text is in colour. The colour is significant. Red for the main title of the sheet, Green for instructions, Black for text which you should not alter or is the result of calculations. Pale blue shaded cells are used where there is a formula embedded – whatever you do, don’t change cells with pale blue shading! Text you enter will come up black. Cells with error messages will be highlighted as we work through the individual sheets.
3.2 The exercise
Part of the first spreadsheet with details of seven analyses taken from the BCIS files is shown below. This spreadsheet is concerned only with gathering the bare details of any analyses which the quantity surveyor thinks may be useful in his later deliberations. The first of these is to determine what should be used as the cost/m2 of GFA to be used when setting up the cost limit for the new project. With this in mind, let us look at the analyses broadly to see if any one is more suitable than the others as a basis from which to work. If no single analysis is found then the quantity surveyor must decide on the level of price he is to use and go on from there. The analyses date back some 5–6 years from the situation current at the time of writing. This is ideally about as far back as one would wish to go. The longer the period of time over which an up date to current cost is applied, the less accurate it becomes and then remember, this cost has to be forecast up to the tender date on even less reliable data. Because of the paucity of data on buildings with this particular end use, all available analyses have been included in the list above. It is interesting to note that two are in Edinburgh but even worrying that the current costs given are £1067 and £1477 per m2 of GFA.
UPDATE OF ANALYSES - GFA COST ONLYProposed Health Centre, Dalkeith Mains Edinburgh
Date: / 05-Mar-03
Job reference HC321 / Time: / 16:48:38
Current cost index: / 199
Job Location Factor: / 0.98 / There is space for 20 analyses
Original / Updated
Original / Original / Costs per / Costs per
LIST ANALYSES REFERENCES / Analysis / Location / m2 of / m2 of
below, starting in row 11 / Index / Factor / GFA / GFA
C-1-455, Swinton South Yorkshire / 129 / 0.94 / £600.18 / £965.26
C-1(2)-849, Mossend, Motherwell / 192 / 0.96 / £994.66 / £1,052.40
C-2(1)-2,136, Craigmiller, Edinburgh / 137 / 0.98 / £734.71 / £1,067.21
A-2-881, Wilsden, West Yorkshire / 154 / 0.87 / £739.78 / £1,076.82
C-1-432, East Bridgeford, Notts. / 147 / 0.94 / £870.16 / £1,228.10
D-1(2)-309, Dennistoun, Glasgow City / 137 / 1.00 / £932.12 / £1,326.88
C-2-747, Liberton, Edinburgh / 154 / 0.98 / £1,143.19 / £1,477.24
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
#DIV/0!
Figure 3.1 Update of the Cost/m2 of GFA only of selected analyses
From the TPIs (Tender Price Indices) in each case you will note that the Craigmiller centre was built well before the Liberton one but at about the same time as the Glasgow one which is about as expensive as the Liberton one! The Motherwell building is about the same cost/m2 of GFA as the Craigmiller one, although built several years apart. What are we to make of all this? The situation is ‘up for grabs’, and the quantity surveyor has to look now at more detail – specificational detail and facilities offered in each of the analysed buildings – to see if one is close to what the client wants. Let us look first at the Motherwell and Craigmiller buildings. There must be something which brings their current costs so close together and which might provide a basis from which to work.
Before we go on, note that the date and time the sheet was made up is printed automatically for you. Save the spreadsheet under a unique file name and print out a copy for your files.
Element / Craigmiller / MotherwellSubstructure / RC founds, plain concrete beds, PCC plank flooring / Plain strip and pad; plain conc. GF slab; Visqueen 1200 DPM
Frame / Steel columns and beams / 10.66 tonnes column and beam with intumescent paint giving 60 min fire protection
Upper floors / PCC plank decking / 191 m2 contractor designed PCC/composite conc. sus slab floor
Roof / Timber structure, metal covered, aluminium guttering / 841 m2 18 degree timber trussed roof with sarking, conc. interlocking tiles; uPVC gutters and downpipes: Velux roof lights
Stairs / Steel in 3 flights / PCC/composite with steel balustrades.
External walls / Facing brick/insulated cavity, 140 block inner skin and 9 no glass bock screens / Facing brick/block cavity walls; 45mm polystyrene insulation; Catnic steel lintels
Wdws/Ext drs / Contractor designed wdws, 5 flush s/w doors / DG powder ctd al. wdws, doors and screens
Int walls/parts / 100, 140 & 190 block generally, glass block, timber and metal stud parts. WC cubicles, glazed timber screens / Block parts; 66m 30 min fire resist metal stud partition; folding partition to staff room.
Int doors / Solid core flush doors in s/w frames / Flush doors
Wall finishes / Plasterboard, plaster, ceramic tiles / 226m2 gypsum wallbrd; 448 m2 Thistle hardwall to blkwrk; 4 m2 ceramic tiles; 510 m2 vinyl silk emulsion to plaster and 820m2 to p/brd
Floor finishes / Isocrete Gyvlon screed, lino, ceramic tiles, carpet / 188 m2 cem/sand screed; 469 m2 levelling screed; 529 m2 carpet; 114 m2 vinyl sheet.
Ceiling finishes / Plasterboard, steel & plasterbrd sus. ceilings / 401 m2 P/brd; 448 m2 vinyl silk emulsion; 153 Gyproc MF sus. clg; 119 m2 Ecophon white min. fibre sus. Clg.
Fittings / Reception desks, shelving, wrktops, kit. fttgs / Shelving, mirrors etc.
San Appl / 16 whb; 3 clnrs sinks; 2 shower units; 16 WCs; 1 urinal bowl; 15 inset basins; 5 SS sinks / Vitreous china WCs & whbs; SS sinks; shower unit; bathroom accessories.
Disposal Inst / Aluminium R/W; uPVC SVP / uPVC SVP
Heat source / Gas boiler / Gas boiler
Space htg/air trtmnt / LPHW htg; ventilation system / LPLTHW central htg sys with rads.
Elect inst / Light and power / Light and power; Distribution £9803; lighting £12543; power £10002; containment £3835; mech servs. £225
Gas installation / ? / Natural gas installation
Lift and conveyor / Lift / N/A
Protective inst / Door entry, security network / Lightening protection £2528
Comms inst / Computer conduits; TV; telephone; call sys; disabled sys; general call sys; audio/visual door sys. / Fire, intruder, panic alarms; data cabling; CCTV
Special inst / Panic alarm sys / Satellite TV; BMS
Builders work / General / General
Site works / Macadam roads; PCC paviors and slabs; seeding and turfing; steel fencing / 1219 m2 macadam paving; 144 m2 PCC blocks; seeding turfing and planting; timber fencing
Drainage / 494m clay and uPVC pipe; 19 gullies; 10 m/holes / UPVC pipe; 7 brick m/holes
Ext services / Gas; water; electricity; telephone / Gas; water; electricity; telephone; street lighting
Prelims / 3.62% of remainder of contract / 12.89% of remainder of contract.
GFA / 2136 m2 / 849 m2
Storeys / 2 / 2
Contract / JCT private with quantities; selected competition; 7 tenderers; base June 1997; firm offers / JCT private with quantities; negotiated; firm offers; base April 2002.
Contract period / 15 months / 9 months
Measured work* / 94% / 74%
Prime cost and Prov. sums* / 5% / 26%
Preliminaries and Contingencies / 7% / 26%
*As a % of contract sum less Preliminaries and Contingencies
Figure 3.2 Comparison of specification etc. of two updated analyses
There are a number of very significant differences between the two contracts and one of these will make the difference between using one of these analyses or not for the next stage of the cost plan, setting the cost limit. The differences are:
· Craigmiller’s foundations are of a more expensive construction.
· Frame is comparable.
· Upper floors are comparable.
· Craigmiller’s roof just slightly more expensive.
· Stairs are comparable.
· External walls comparable.
· Windows and External doors comparable.
· Internal walls and partitions are comparable.