How to Inspect Your Underlayment Installation for Problems (Visual Guide)

DIY Underlayment Installation Inspection Checklist

Regular visual inspection of your underlayment installation can catch problems months or years before they become expensive emergencies. Most underlayment installation issues develop gradually and produce visible warning signs that a trained eye — or even an informed homeowner — can identify during a 15-minute walkthrough. This guide teaches you exactly what to look for, where to look, and what each sign means for your repair timeline and budget.

Plan to inspect your underlayment installation at least twice per year — once in spring and once in fall. Use a phone camera to document conditions each time so you can compare photos across inspections and spot progressive changes that might otherwise go unnoticed. After severe weather events, conduct an additional inspection to check for acute damage that requires immediate attention.