Composite vs uPVC doors

A composite door has a solid timber core in a GRP skin, typically 44mm thick. A uPVC door has a plastic outer with a foam or cardboard-honeycomb infill and steel reinforcement in the frame. That structural difference drives everything else.

Where composite genuinely wins

Impact. A solid core resists a boot in a way a hollow panel does not. Thermally the insulated core edges it. Colour runs through the GRP, so a scratch does not show white. Feel — a composite door is heavier and shuts with a solid sound, which sounds trivial and is the thing people actually notice.

Where uPVC is the rational choice

Back doors, side doors, utility doors, rentals, and anywhere out of sight. It costs meaningfully less, it insulates well, and a good modern profile is a perfectly sound door. Spending composite money on a door onto a bin store is not a considered choice.

The thing that actually decides security

Neither the slab nor the material. It is the cylinder. Most forced entries through modern doors are snapped cylinders, not broken panels. A TS007 1-star cylinder in a 2-star handle, or a 3-star cylinder on its own, is what stops that. A composite door with a cheap cylinder is less secure than a uPVC door with a good one — and the good cylinder costs a fraction of the difference between the two doors.

Lifespan

Composite around 30 years, uPVC around 20–25. In both cases the hardware and the sealed units usually need attention long before the door does.