Which type of documentation is typically required to prove that proper materials were used and installed according to code?

• A. Invoices only
• B. Verbal attestations
• C. Material certificates, test reports, inspections, and as-built drawings
• D. Contractor payroll records

Answer: (C)

To prove that proper materials were used and installed according to code, you need verifiable and traceable documentation that covers material specifications, performance, and the actual installation. Material certificates show the exact materials used meet the required standards and can be traced to the batch or lot, ensuring the right components are in place. Test reports provide objective results from tests on those materials or the installed system, confirming they meet the required performance. Inspections document that qualified personnel or authorities reviewed the work at various stages and found it compliant with applicable codes. As-built drawings capture the exact, final installation, including any field changes, so you can verify the installation aligns with the design and code requirements over time. Invoices only show purchases, verbal attestations lack verifiability, and payroll records relate to labor, not material quality or code compliance. Together, material certificates, test reports, inspections, and as-built drawings give a complete, auditable record of compliance.