Disclosed is an interlocking glazing panel comprising a pair of transparent or translucent lites, and rigid structural spacer located between, and firmly attached to, said lites to define a gap therebetween, said rigid structural spacer extending around at least part of the periphery of said glazing unit and having over at least a portion thereof an interlocking profile to provide a firm interlocking connection to another interlocking panel having a complementary like interlocking profile, wherein said glazing panel can be inserted as a structural member in a wall or roof constructed of interlocking panels.