eaves
簷 centers on the projecting edge of a roof: the eaves that overhang and shelter the walls below.
簷 combines 竹 (bamboo) with 詹, which likely contributes the sound. The character originally referred to eaves, perhaps made of bamboo in early construction.
The top 竹 suggests bamboo, and the bottom 詹 looks like a roof with a protruding edge. Picture bamboo eaves extending out from a traditional building.
For エン, imagine the eaves ending in a gentle curve: end -> エン, and the roof edge finishes with a smooth overhang.
upturned eaves; high roof