Know the core and cap
Conventional wood-plastic composite contains wood-derived material blended with polymers. PVC decking has a polymer-based core without that conventional wood-fiber blend. Both may use protective caps. Cap coverage, core, profile and surface formulation influence performance, so record all four before comparing claims. Mineral-based composites are another construction and should be identified separately.
Moisture and movement
A wood-free core can be attractive for moisture-prone settings, but approval for pool surrounds, docks or direct water contact still needs checking. Both families need clear drainage and correct installation. Thermal movement and reflected heat deserve particular attention. Do not use generic end gaps or treat fascia as if it were an ordinary deck board.
What to compare in person
Put labeled samples of the actual color in the intended sun. Compare walking feel, surface texture, realistic grain, visible end treatment and scratch repair options. Ask for the current cleaning guide and warranty. A cooler-surface claim usually compares particular colors and products under specific conditions; it is not a universal temperature promise.
A practical decision
Shortlist one product from each family at the same installed scope. Compare support requirements, fasteners, finish details and local availability. If the PVC option costs more, identify the property or appearance you are buying. If a composite is cheaper, check whether extra support or trim changes the total.