Warranty Period Calculator

AIA Document A201 Section 3.5 provides a one-year warranty against defects in materials and workmanship from the Date of Substantial Completion. This is the standard 'warranty period' or 'guarantee period' in most US construction contracts. Specific systems may have longer manufacturer warranties: roofing (10-20 years), HVAC equipment (5-10 years), structural concrete (longer implied by statute of limitations). Equipment manufacturer warranties run concurrently with the construction warranty.

Under AIA A201, the warranty period starts on the Date of Substantial Completion, which is certified by the architect. Note: if the owner takes occupancy of a portion of the work before Substantial Completion, the warranty for that portion begins when the owner takes occupancy. The warranty runs from Substantial Completion, not from Final Completion or the date the contractor finishes the punch list.

AIA A201 Section 3.5 requires the contractor to warrant that the Work will be free from defects in materials and workmanship for one year from Substantial Completion. The warranty covers latent defects discovered after completion. It does not cover: damage from owner misuse or abuse, normal wear and tear, cosmetic issues existing at the time of Substantial Completion (which should be on the punch list), or damage from modifications made by the owner after acceptance.

Beyond the express contract warranty period, contractors may have implied warranty obligations under state law that extend longer. Statutes of limitations for construction defects vary by state: typically 3-10 years from the date of discovery of the defect (discovery rule) or 6-15 years from substantial completion (statute of repose). Some states have specific construction defect statutes. The statute of repose caps the time regardless of when the defect was discovered.

A warranty reserve is a fund set aside by a contractor to cover the cost of expected warranty repairs during the warranty period. Construction industry practice is to reserve 0.5-2% of project revenue for warranty costs. High-risk project types (complex mechanical systems, waterproofing, new materials) warrant higher reserves. Without a warranty reserve, unexpected warranty calls can create cash flow problems, especially for contractors with thin margins.