Are GAF Timberline shingles asphalt shingles, and what are they made of?
Short answer. Yes. GAF Timberline shingles are laminated asphalt shingles built on a fiberglass mat, coated with asphalt and surfaced with ceramic coated mineral granules, with a factory sealant strip that bonds each course to the one below. Different Timberline lines change the recipe, such as a reinforced mat in UHDZ or SBS modified asphalt in AS II.
What is inside a Timberline shingle
- Fiberglass mat: the backbone that gives the shingle strength and keeps it from rotting. Timberline UHDZ uses GAF's UltraMat, a heavier mat that helps it reach Class 4.
- Asphalt: the waterproofing. Timberline AS II uses SBS modified asphalt, a rubberized formula that flexes under impact.
- Granules: ceramic coated stone on the surface that blocks UV, provides color and adds fire resistance. Some granules carry copper for algae resistance.
- Sealant or adhesive strip: bonds each shingle to the one below once the sun warms it. GAF calls its version Dura Grip on lines with LayerLock.
- Back surfacing: fine mineral on the underside that keeps shingles from sticking together in the bundle.
Laminated construction
Each Timberline shingle has two layers: a full top layer with cutouts, and a backer strip beneath. Where they overlap, the shingle is thicker, which creates shadow lines. On HDZ and UHDZ, GAF's LayerLock technology mechanically fastens the layers and creates the StrikeZone nailing area.
How Timberline lines differ
- Timberline NS: value line, subtler shadow.
- Timberline HDZ: mainstream line, Class 3 on labeled packages.
- Timberline UHDZ: thicker, dual shadow line, Class 4 with UltraMat on labeled packages.
- Timberline AS II: SBS modified, Class 4 on labeled packages.
Asphalt in Georgia's climate
Heat and UV slowly dry out asphalt, which is why ventilation and granule coverage matter. Read heat and humidity and roof life and architectural vs 3-tab shingles.