A change during building work can affect price, timing and other parts of the design. Recording it clearly gives both homeowner and contractor a better chance of understanding what has been requested, agreed and completed.
Identify the original agreement
Keep the accepted quotation, drawings, specification and contract together, with their dates and revision numbers. When a change arises, describe which part of that agreed scope it affects. Distinguish an extra request from work already included or the correction of defective work. If there is disagreement, seek advice rather than automatically treating every additional invoice as an agreed variation.
Describe the change precisely
Give the change a reference and date, identify its location and attach a marked-up drawing or photograph where useful. State the requested outcome and any design information still needed. A message saying “use the better one” is hard to interpret later. Confirm the actual specification, quantity and extent before treating a price as complete.
Ask for cost and programme effects
Request a written breakdown of the proposed adjustment, including omissions, additions, VAT where applicable and any allowance that remains uncertain. Ask about delivery dates, disruption and consequences for other trades. A small visible change can require work elsewhere. Do not assume that agreeing a material price also agrees every labour or programme implication.
Follow the contract’s approval process
Check who has authority to instruct changes and how instructions must be issued. Keep the decision in the required form and circulate it to the people who need to act. A practical change record supports the contract; it does not override its terms or decide a legal dispute. Obtain advice where authority or payment obligations are unclear.
Deal with urgent discoveries carefully
If work reveals a safety concern or an unexpected condition, ask the contractor what immediate protective action is needed and what further investigation is proposed. Record the discovery and preserve relevant evidence safely. Do not pressure anyone to continue unsafe work while a price is debated. Emergency action and approval of a permanent solution may require separate decisions.
Update the project record
Maintain a running total of agreed changes and distinguish it from quotations still awaiting a decision. Update drawings, the programme and the expected final account as appropriate. At completion, check that the record explains what was actually built. A short, consistent log is easier to manage than reconstructing decisions from months of messages.
Further reading
Citizens Advice: agreeing building work. Official guidance checked 21 October 2026. Requirements vary by project and UK jurisdiction; use advice relevant to your property.
Related: How to compare builders’ quotes before a home renovation.
Image: AI-generated editorial illustration.