Re-Roofing
Installing a new layer of shingles over an existing layer without removing the old material.
Overlay vs. Tear-Off
Re-roofing (also called an overlay or "roof over") means installing new shingles directly on top of an existing layer, without removing the old roof down to the deck. It's faster and cheaper than a full Tear-Off because there's no disposal cost and less labor — but it also means any existing decking damage, hidden leaks, or failed flashing stay buried under the new layer.
Ohio's Code Limit
The Ohio Residential Code (adopting the International Residential Code) permits a maximum of two roofing layers total. If your home already has two layers of shingles, code requires a full tear-off before a third can be installed — no exceptions. Even on a first overlay, most manufacturers reduce or void shingle warranties on overlays, and an overlay adds meaningful weight to the structure, which matters on older framing.