Service life depends far more on ventilation, installation quality and sun exposure than on which product went on. An architectural asphalt roof over a properly vented attic on a shaded northern slope will considerably outlast the identical shingle over an unvented attic facing full afternoon sun, because heat trapped underneath cooks the asphalt from below. Standing-seam metal is a genuinely different tier and it is normal for one to outlast two or three asphalt roofs on the same house. Single-ply membrane on a flat or low-slope section lives or dies on its seams and its drainage rather than its age. The most reliable way to know where yours stands is an inspection that looks at the attic side as well as the surface, because that is where the ventilation story is visible.
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