| Architectural Asphalt ShinglesGAF Timberline HDZ / CertainTeed Landmark | $4.89 – $7.50 / sq. ft. | 25 – 30 Years | Needs Class F 130 mph wind seal and copper/zinc granules to resist Delaware algae staining near water bodies. | Detached single-family homes, rentals, and traditional Dover neighborhoods. |
| Standing Seam Metal24-Gauge Galvalume / Kynar 500 | $12.00 – $19.50 / sq. ft. | 50+ Years | Concealed fasteners resist salt spray corrosion; sheds Delaware snow cleanly without ice dam formation. | Modern farmhouses, coastal homes, historic porches, and accent gables. |
| Low-Slope / Flat RoofingCommercial TPO & 060 EPDM | $6.50 – $14.00 / sq. ft. | 20 – 30 Years | Requires strict slope-to-drain design to prevent ponding water during Dover's 36.0" annual rainfall. | Commercial retail, downtown storefronts, rear home additions, and sunrooms. |
| Synthetic Composite SlateDaVinci / Brava Polymer Composite | $14.00 – $24.00 / sq. ft. | 50 Years | Class 4 impact rated; unaffected by freeze-thaw cracking without the extreme weight of natural stone slate. | Historic Dover homes, executive residences, and steep-slope Victorian properties. |