What is the difference between a new roof and a reroof?
Short answer. A new roof, or full replacement, removes every existing layer down to the deck before new materials go on. Reroofing usually means installing new shingles over the existing layer without a tear-off, though some contractors use the word loosely for any replacement, so always ask whether the quote includes removal.
Why the words get confusing
In building codes, reroofing covers any work that replaces or covers an existing roof, and a recover is the specific case of laying new roofing over old. In everyday sales talk, a reroof often means that overlay. Two quotes with the same wording can describe very different jobs, so read the scope line by line.
What each job includes
- Full replacement: tear-off to the deck, deck inspection and repair, new drip edge, leak barrier, underlayment, flashing, pipe boots, ventilation, shingles and caps.
- Overlay: new shingles nailed through the existing layer. Flashing is often reused, the deck is never seen, and the old roof's lumps can show through.
Where overlays are not allowed
The residential code does not permit a recover when the existing roof is water-soaked or deteriorated, when it is slate or tile, or when there are already two or more layers. Some HOAs and shingle manufacturers add their own conditions, so check before choosing an overlay.
Why most Georgia roofs get a full replacement
- Hidden deck rot and old leaks get found and fixed.
- Flashing and edge metal are replaced instead of patched around.
- A single layer runs cooler and lies flatter, which helps shingle life.
- The next roofer does not face a two-layer tear-off.
The cost and tradeoffs of going over the old layer are explained in roofing over existing shingles, and the layers themselves in roof anatomy explained.