Both Hume and Corinthian doors have five-year product guarantee on their doors. As with any product there are strict conditions. The product warranty documents are available for download on the product pages along with care and maintenance guides.
The most important condition outlined in the warranties is that all doors must be painted, sealed or stained within a month of purchase in order to protect the integrity of the door.
The warranty documents can also be accessed here:
Hume:
Corinthian: