A builder can price a job accurately, manage trades well, and still finish in the red.
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Contract variation procedure with worked example
Featured walkthrough · 26 min
In most cases, the cause is the same: variations that were completed but never properly controlled.
Variations are not the problem. Scope changes on a custom home are inevitable. The problem is the system around them, or more accurately, the absence of one.
Most variation failures follow the same pattern. A client requests a change on site. The project manager agrees to proceed because the change seems minor or stopping work to process paperwork feels disproportionate. The trade completes the work. The cost gets absorbed into the job. At the end of the project, the builder reconciles the final account and finds the job is short by an amount that correlates almost exactly with the unprocessed variations from the previous six months.
The individual amounts rarely look significant in isolation. A $400 change to a tapware selection. An additional day of excavation after rock was struck. A revised balustrade detail that required custom fabrication. Separately, each one feels manageable. Cumulatively, across a $1.2 million project, they represent the difference between a healthy margin and a break-even job.
The second failure point is verbal approval. A client says yes on site. Work proceeds. The variation is never formalised in writing. At the end of the project, the client disputes the charge because they don't remember approving it, or because the final account is higher than expected and they are looking for items to challenge. Without a signed variation order, the builder has no position to stand on.
The third failure point is underpricing. A builder prices a variation quickly, without applying the same rigour used in the original estimate. Preliminaries are not added. Margin is forgotten. The variation is issued at cost. This happens most often on small variations where the builder wants to appear reasonable, and most expensively on large variations where the time pressure is highest.
A controlled variation process starts with one non-negotiable: no work proceeds on any change to contracted scope until a variation has been identified, priced, and submitted for approval. Not after. Not concurrently. Before.
The pricing step is where discipline matters most. A variation is priced the same way as the original estimate: labour, materials, plant, subcontractor costs, site overheads, and margin. Preliminaries are applied where the change extends the programme. Margin is applied at the same rate as the contract. A variation is not a favour. It is a commercial transaction.
Approval must be in writing before work proceeds. Verbal approval with nothing following it in writing is not a variation system. It is a dispute waiting to happen.
Variations should not be held and invoiced at Practical Completion as a lump sum. They should be invoiced progressively so the cash position of the project reflects actual cost at every stage. A builder who invoices $180,000 in unprocessed variations at the end of a job is not running a variation system. They are running a credit facility for their client, funded by their own cash flow.
A residential builder running ten custom homes a year, averaging $900,000 per contract, with a 12% margin target, needs to recover $108,000 per project to hit plan. On a project where $60,000 in variations were completed but not recovered, the margin drops to 5.3%. That is not a rounding error. It is a business model problem that compounds across every project where variation discipline is absent.
The builders who run clean final accounts are not the ones who have fewer variations. They are the ones who process every variation the same way, every time, regardless of the relationship, the size of the change, or the pressure to keep work moving.
The system removes the discretion. That is precisely why it works.
— BuildHawk
