South Glamorgan Premier suppliers preferred approved MPN fitting the Capital City and County with the full range of endurance doors. Do Composite Doors Warp? Composite Doors Endurance. In fact, they don’t suffer from any issues that traditional timber or uPVC doors and when you buy endurance you are buying a door that will stand the test of time. Get our very best value quality affordable prices and quotes online or call the free composite door sales phone number 0800 158 8800.