How to control project variations and scope changes.
Projects change. Site conditions differ from drawings, users request additional functionality, quantities move and suppliers discover technical constraints. A variation process is therefore not a sign of bad project management; uncontrolled variation is.
1. Define the approved baseline
Change control only works if everyone knows what the original agreement contained. Keep the approved scope, drawings, bill of quantities, specification, programme and commercial schedule as the baseline.
2. Capture the change request
Record who requested the change, when, why and exactly what is different. Give it a unique reference number so emails, quotes, approvals and site instructions can be connected later.
3. Identify whether it is actually a variation
Not every disagreement is extra work. Compare the request with the contracted scope and responsibilities. The supplier may already be obliged to perform it, or the request may genuinely add or remove work.
4. Assess technical impact
Determine what designs, products, interfaces, resources, tests or documentation change. Check whether the variation invalidates earlier approvals or affects other work packages.
5. Assess schedule impact
Record additional duration, procurement lead time, access requirements and effect on critical milestones. A change can be inexpensive in material cost but expensive in programme disruption.
6. Assess commercial impact
Prepare a transparent cost build-up using agreed rates where available. Include additional material, labour, freight, subcontracting, rework, project management and any credit for omitted work.
7. Identify the approval authority
Site personnel may be able to request work without having authority to approve additional expenditure. Define who may approve which value or type of change and obtain that approval before committing cost where practicable.
8. Record status clearly
Use states such as:
- Requested
- Under assessment
- Priced
- Approved
- Rejected
- Implemented
- Closed
This prevents a quotation from being mistaken for an instruction to proceed.
9. Handle urgent changes explicitly
Some safety, production or site conditions require immediate action. Where the contract allows emergency instruction, record the instruction, provisional commercial basis and required ratification instead of relying on an informal verbal agreement.
10. Update the baseline after approval
An approved variation should update the relevant scope, budget, programme, drawings, deliverables and risk register. Otherwise the team continues managing against an obsolete baseline.
11. Reconcile variations before closeout
Before final invoicing, confirm that every approved variation appears in the commercial records and every rejected or cancelled request is closed. The final handover pack should reflect the as-delivered scope, not merely the original tender drawings.
A simple variation register is often enough
Useful columns include reference, date, requester, description, reason, cost effect, schedule effect, quotation reference, approval authority, approval date, status and implementation evidence.
Good change control protects both parties
The client retains control over budget and scope, while the supplier gains evidence that additional work was authorised. The process works best when the original scope of work was clear enough to establish where the baseline ends.