How is a new roof different from the old roof it replaces?
Short answer. A roof installed today is a more complete system than most roofs from 20 or 30 years ago: laminated architectural shingles instead of 3-tab, synthetic underlayment instead of felt, self-adhered leak barrier where water concentrates, required drip edge, matched starter and ridge products, and ridge ventilation. The result is better wind resistance and fewer weak points, as long as it is installed to the manufacturer's instructions.
Then and now
- Shingles. Then: thin 3-tab shingles with cutouts. Now: thicker laminated architectural shingles with higher wind ratings and, in some lines, impact ratings.
- Underlayment. Then: asphalt-saturated felt that tears and wrinkles. Now: synthetic underlayment that is lighter, stronger and lies flatter.
- Leak barrier. Then: often felt alone in valleys. Now: self-adhered membrane in valleys, around chimneys, skylights and pipes, and at walls.
- Drip edge. Then: often missing, with shingles hanging over the fascia. Now: required at eaves and rakes.
- Starter and ridge. Then: cut from field shingles. Now: dedicated starter strips with sealant at the edge, and matched hip and ridge caps.
- Ventilation. Then: a few box vents or a gable fan. Now: ridge vent balanced with soffit intake where the house allows.
- Flashing and boots. Then: reused or tarred over. Now: new step flashing and boots, with sealant as backup rather than the main seal.
- Code. Georgia now enforces the 2024 International Residential Code with state amendments, effective January 1, 2026.
What stays the same
The deck, the framing and the shape of the house. A new roof cannot fix sagging rafters or an attic with no soffit intake by itself, and it is only as good as the crew that installs it.
Why it matters for your decision
If your current roof is an original 3-tab with no drip edge and a few box vents, a replacement is an upgrade, not just new shingles. When comparing bids, check that each includes these modern parts. See architectural vs 3-tab shingles, synthetic underlayment vs felt and ridge vent vs box vents.