This European Standard specifes principle material requirements for timber and wood-based products in internal windows, doors and doorframes (with or without fixed parts), including appearance, biological durability and other physical characteristics. This European Standard applies to factory assembled internal windows, door leaves and doorframes uncoated or intended to be coated. If doors are covered by other decorative veneers or films the respective veneer or film Product Standard shall apply. EXAMPLE Timber veneers may be graded to EN 635: Parts 1, 2, 3 and 5, and ENV 635 4.