四分律刪繁補闕行事鈔 1.157

1.157

半覆中間障、若伸手不相及者。謂半僧簷下，半僧階下，中間施隔；或復無障，伸手不及。並非同住之相。

Half-covered with an obstruction between, or beyond arm's reach: this refers to half of the saṃgha being under the eaves and half of the saṃgha below the steps, with a partition placed between them; or again, without an obstruction, beyond arm's reach. None of these constitute the characteristic of dwelling together.