Most homeowners overestimate the guarantee and underestimate the law. The Consumer Rights Act 2015 already requires reasonable care and skill and gives you years to claim; a guarantee only adds something real when an insurer stands behind it. What the law gives, what paper adds, and the questions that separate the two. Checked August 2026.
Consumer Rights Act 2015 s.49-56; Limitation Act 1980; Prescription and Limitation (Scotland); all checked August 2026 on legislation.gov.uk. Found defects at handover? Work through the snagging checklist and hold the final instalment until they are fixed. Firm no longer exists? Builder gone bust.
Keep the guarantee, the policy behind it and every certificate together in your renovation record: a guarantee you cannot find is a guarantee you do not have.
The Consumer Rights Act 2015 puts them in every job automatically: the work must be done with reasonable care and skill (section 49), within a reasonable time if none was agreed (section 52), and at a reasonable price if none was agreed (section 51). If the work falls short you can require it to be redone at the builder’s cost, or claim a price reduction. No contract term can remove the care-and-skill duty.
For breach of contract: up to six years from the breach in England, Wales and Northern Ireland (twelve if the contract was signed as a deed), and five years in Scotland. That is the backstop the law gives you, guarantee or not. Report defects promptly and in writing regardless; waiting weakens every claim.
Only as strong as who stands behind it. A guarantee written by the builder is a promise from a company that may not exist in year six. An insurance-backed guarantee or structural warranty is a promise from an insurer, and survives the builder’s insolvency, which is exactly the moment you need it. Ask which one you are being offered, and ask to see the policy, not the brochure.
No. A guarantee comes on top of your statutory rights, never instead of them. Any wording that suggests you are signing rights away is itself a red flag about the firm.
Report it in writing straight away with photos and a date, give the builder the first chance to fix it (that is also your legal remedy: repeat performance at their cost), and keep the correspondence. If the firm no longer exists, go to the insurance-backed guarantee if you have one, and see the gone-bust guide for the rest.