E
FIXED CONSTRUCTIONS
Load children
E04
BUILDING
Load children
E04D
ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
Load children
E04D13/00
Special arrangements or devices in connection with roof coverings; Protection against birds;; Roof drainage; ; Sky-lights;
Load children
E04D13/17
Ventilation of roof coverings not otherwise provided for
Load children Filter patents View as hierarchy
E04D13/174
on the ridge of the roof
Load children Filter patents View as hierarchy