DIFF Subgroup
E04D 13/1473 Full Title
Special arrangements or devices in connection with roof coverings; Roof drainage (ventilation tiles E04D1/30; ventilation slabs E04D3/40; internal channels E04F17/00) > Junctions of roof sheathings to chimneys or other parts extending above the roof > specially adapted for inclined roofs
Of 2 combined children, 0 exist in both systems.
2 codes are CPC-only extensions.