GuideUpdated 25/10/2026
How do I choose a builder for an extension?
Short answer
Get a written, itemised quote based on drawings, check who you are contracting with and who will run the job, agree a programme and payment stages tied to completed work, and make sure building control and any party wall matters are in hand before work starts.
Compare like with like
Quotes from different builders are only comparable if they price the same drawings and specification. Ask for an itemised breakdown with inclusions and exclusions.
Check the contract
- The legal name and address of the company you are contracting with.
- Scope of works, drawings and specification.
- Price, payment stages and how variations are priced.
- Start date and programme.
- Who arranges building control and party wall notices.
- How defects are put right.
Payments
Pay in stages as work is completed. Be wary of large cash payments upfront.
Our approach
Your contract is with S&K Property Investments and Improvement Ltd, with a written quote, programme and payment stages before anything starts. See how it works.
Sources and further reading
This guide is general information, not legal or tax advice. Rules change and depend on your property; we confirm what applies to your project at the survey.
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