The promise is broad but the coverage is unclear
Ask the contractor to translate the promise into specific covered work and a defined response. Identify whether the warranty concerns installation, a named material or another part of the project, and who is responsible for each. Do not infer a comprehensive repair obligation from a long duration or a phrase such as guaranteed quality. The written document should explain the obligation rather than leave it to a later sales conversation.
Notice next: Request the complete terms before signing and keep the approved scope and warranty together. Have unclear legal meaning reviewed by an appropriate local adviser.