Choose the assembly that fits the property—not the trend.

The one that was installed properly on a roof it suits. Material sets a plausible range — a standing-seam metal roof will normally outlast a three-tab shingle — but within that range, installation and detailing decide the outcome far more often than the product does. Most roofs that fail early do not fail in the field of the covering. They fail at a penetration, a valley or a termination that was rushed.

Often, but it is a bigger question than the covering. A heavier system needs framing that can carry it, a shallower pitch rules some materials out entirely, and changing material usually changes the flashing details, the ventilation path and the edge. It is a design decision with a cost attached, not a colour swap, and it wants deciding before the tear-off rather than during it.

Often it already is not. A house can carry shingles on the steep planes and something else entirely over a low-slope porch, carport or rear addition, because asphalt has a minimum pitch below which it is not the right product. Where two systems meet, that junction is a designed detail rather than something improvised on the day, and it belongs in the scope by name alongside both coverings.

Completely, at the heavy end. Tile and slate bring a dead-load question no roofing contractor can settle, and whether a given frame was built to carry them is determined by a structural engineer before any product is specified. At the lighter end the constraints are different — slope, deck condition, ventilation, and the height a change adds at every flashing. Establish which constraint applies before settling on a material.