Cases / Estimating & costing
Estimating & costing

Price the preliminaries and general conditions

Price the cost of running the job itself - site staff, welfare, plant, scaffolding and insurances - split into time-related and fixed and driven by the programme, then carry it into the bill.

4 steps11 minGeneral contractorCost consultancy / QS practiceProject / construction management firm

How it works, step by step

4 steps across the platform - what you do at each one, and why it matters.

1

List the prelims scope

Preliminaries

Build the list of everything it takes to run the site: management and supervision, welfare and cabins, temporary services, common plant, scaffolding, security, insurances and bonds.

Why: The items you forget in prelims are the ones you fund out of profit. A complete checklist read against the contract is the difference between a covered site and a leaking one.

InContract & prelimsOutline programmeOutPrelims schedule
2

Split time-related from fixed

Preliminaries

Mark each item as time-related or fixed, then price the time-related ones per week against the programme duration and the fixed ones as one-off set-up and removal.

Why: Splitting them this way is what lets prelims flex if the programme moves. If the job runs four weeks late, you can show exactly what the extra time costs instead of guessing.

InPrelims scheduleProgramme durationOutPriced prelims
3

Check the resources roll up

Resource Summary

Look at the staff, plant and cabins the prelims imply in the resource summary and sanity check the headcount curve against the programme peaks.

Resource Summary screen in OpenConstructionERP: check the resources roll up

Why: A prelims price that needs three site managers in a quiet month is a warning. Seeing the resource curve catches a double count or a gap before it reaches the tender total.

InPriced prelimsOutResource roll-up
4

Carry it into the bill

BOQ

Bring the prelims total into the bill as its own section, kept separate from measured work, and read it back as a percentage of the works value.

Why: Keeping prelims visible as their own line lets a reviewer benchmark them at a glance. Burying them in the rates hides the one number a client always wants to test.

InPriced prelimsMeasured worksOutPrelims bill sectionPrelims as percent of works
Modules

Modules in this playbook

3 / 184 platform modules

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