Pre-sign due diligence
Variation costs
How to control the risk of price changes during a build through contract mechanics and disciplined record-keeping.
What to think about with variations
Variation cost is one of the biggest drivers of budget blowouts. Before you sign, make sure the variation process is clearly written, that PC sums and provisional sums are realistic, and that no work goes ahead without a signed variation record.
Checks to run
- Ask how variations are priced, approved, and documented.
- Check whether PC sums and provisional sums are realistic.
- Keep signed variation records separate from informal messages.
Questions to ask before signing
- What is the variation approval process and who signs it?
- Are PC sums and provisional sums itemised in the contract?
- Does the contract require signed variations before work begins?