Re-Roof or Tear-Off? What Contractors Look at on the Existing Deck
A re-roof (also called a "lay-over") puts new shingles over the existing ones. A tear-off strips everything to the deck. Most jurisdictions allow a single layer over, but the question isn't usually "can I" — it's "should I."
When a re-roof makes sense
• The existing shingle layer is single, flat, and not curling
• The deck below is verified intact
• You want to defer cost, knowing you'll do a full tear-off next time
• The roof has years of reasonable life left and you're just refreshing
When tear-off is the right call
• The existing roof is past two-thirds of its rated life
• There are signs of moisture below (water staining on the underside of the deck visible from the attic)
• The deck has obvious soft spots, deflection, or rot
• You want a roof that lasts the full rated life of the new shingles
What contractors look at on tear-off day
Once the shingles are off, the contractor inspects every inch of decking. They check for:
• Punky or delaminated areas
• Nail pull from wet rot
• Span issues at rafter spacing
• Old penetration patches that aren't watertight
• Adequacy for the new fastening pattern
A good contractor calls you with photos of any issue before re-decking. A bad one quietly covers it over.
What this means for you
The price difference between a re-roof and a tear-off is real, but so is the lifespan difference. Get a confident inspection-based recommendation, not a sales pitch.
What contractors should know
A walked-and-photographed deck inspection beats any closing argument. Customers who see the actual deck make better decisions and trust you longer.
The part nobody can see later
Most of what decides how this holds up gets covered before the job is over. Once it is closed in, the only record of how it went in is the photos taken while it was still open.
Supervisr's roofing QA model works from common industry practice and the installation instructions that ship with the materials. It can analyze roof installation photos for shingle nail pattern, flashing detail at penetrations and sidewalls, underlayment and ice-and-water coverage, ventilation balance, and high-wind construction details. Upload photos of shingle nail pattern, step and kickout flashing, ridge and soffit ventilation, valley construction, and chimney flashing detail, and you'll get a documented evaluation back in minutes.
For a homeowner, that record is a straightforward way to understand what you paid for. For a contractor, it is the milestone documentation that stands behind a workmanship warranty years later, long after the crew has moved on to the next job.
About Supervisr
Supervisr is an AI quality-assurance platform for residential roofing. It works from common industry practice and manufacturer installation instructions, and analyzes roof installation photos to flag issues like incorrect nail patterns, missing flashing, or unbalanced ventilation.
Contractors use Supervisr to document quality at each milestone — backing up a workmanship warranty and building a track record of work they can point to. Homeowners end up with a clear record of what went into their home. See how it works at supervisrapp.com.