The problem: you find out at final bill
Ask a contractor whether a running project is making money and the honest answer is often “we will know when it is closed”. By then the overrun is history. The reasons are structural:
- The budget is a spreadsheet made at tender time and never updated.
- Purchase orders are raised on site or at head office, but nobody adds them up against the budget until the supplier’s bill arrives.
- Labour and plant cost is known only when wages and hire charges are paid.
- Subcontractor bills are certified without checking what the client has certified to you.
- Accounts books costs by ledger, not by project and BOQ item.
Cost control needs cost to arrive against the budget as it is committed, not months later.
How project cost control works
The method is the same whether the project is a building, a road or an industrial fit-out:
- Set a budget at cost. Start from the contract BOQ and the rate analysis behind it, and express the budget by cost head (material, labour, plant, subcontract, overheads) and by phase.
- Record commitments. Every approved purchase order or subcontract order commits cost.
- Record actuals. Goods received, labour days worked, plant used and subcontract bills turn commitments into actual cost.
- Measure progress and revenue. Certified RA bills tell you how much of the contract has been earned.
- Compare and forecast. Variance by head and phase, plus a forecast of final cost and margin.
- Act. Re-plan, renegotiate, raise a change order for extra scope, or chase certification.
The central tool is a cost ledger: one place where every cost for the project lands, tagged to a cost head and phase. For a longer discussion, read Controlling construction project cost with budgets and a live cost ledger.
What to look for in cost control software
- Budget linked to the contract BOQ, not typed separately.
- Automatic cost posting from purchase, stores, labour, plant and subcontracts — double entry is where cost control breaks down.
- Committed and actual cost shown separately.
- Variance by cost head and phase.
- Revenue at certification, so margin is based on what the client has accepted.
- Financial privacy, so site roles can work without seeing margins.
A simple test
Take one cost head on a live project — say, reinforcement steel — and ask a vendor to show, on one screen, the budget, the quantity and value on open purchase orders, the quantity received, the quantity issued to site and the progress achieved. If assembling that answer needs an export to Excel, the software records costs but does not control them. The same test works for labour: compare man-days approved in the muster with the work recorded in daily progress reports for the same period.
How Zaptiz Construction controls cost
Zaptiz Construction builds cost control into the normal flow of work rather than adding a separate costing exercise.
Budget from the contract BOQ
When a contract is awarded, the project budget is derived from the contract BOQ at cost. Variance is reported by cost head and by phase.
A cost ledger that posts itself
Committed and actual cost are posted automatically from:
- Purchase orders — approved POs commit cost.
- Goods receipts — posting a GRN updates stock and PO receipts and moves committed cost into inventory.
- Labour muster — approving a day’s muster posts labour cost.
- Equipment logs — daily used, idle and breakdown logs for owned or hired plant at deployment rates.
- Subcontract bills — with a warning when what you certify to a subcontractor runs ahead of what the client has certified to you.
Nobody re-enters these figures for costing; they are a by-product of doing the work in the system.
Controls before cost happens
Purchase orders take an approval tier based on order value against your threshold, and a duplicate-order guard catches repeat orders. Material requests are split into from-stock and to-purchase, so material already in your stores is issued before anything new is bought. Stores use weighted-average valuation.
Financials and alerts
Project financials show budget against cost, revenue at certification, progress and forecast margin. A Needs Attention panel raises rule-based alerts for what needs action today.
AI reports
The Cost Overrun Watch agent reports variance drivers and forecast by project, and the Labour and Plant Productivity agent compares man-days against norms and highlights idle plant cost and repeat breakdowns. The figures come from your records; the AI explains them. See Zaptiz AI.
Privacy and limits
Money fields are removed on the server for roles without financial access, so site engineers and store keepers can post muster and receipts without seeing margins. Cost control is per project: there is no consolidated cross-project roll-up, and Zaptiz Construction does not produce a company P&L or balance sheet. Price escalation is flagged but not calculated. Payroll is not included; muster posts labour cost, and wages are paid through your payroll system.
Get started
Pick a live project with a clean contract BOQ, set it up following Setting up your first project in Zaptiz Construction, and route the next month’s purchase and muster through Zaptiz. Book a demo to see the cost ledger with your own figures, or contact us for a quote.