The colonisation of this species has increased over the last few decades due to human transport and trade, most likely arriving during colonial times, via inert phoresy on ships, planes, trains, and merchandise.

[14] Another speculated arrival method is that of ballooning, a means of dispersal in Araneae where a spiderling lets out a thread of silk called gossamer, which is carried away by wind or a thermal updraft, causing the spider to become airborne.

[14] In most foreign nations including New Zealand, the grey house spider is a synanthropic species and is common in urban habitats and agroecosystems.

[13] The species primarily are found living in tree trunks, rock walls, retreats, leaves, and tangled webbing in green shrubs.

[6][8] In the United States, Badumna longinqua seems to be less reliant on a synanthropic relationship with people and can also be located in woodlands, along immediate coastal areas, within agricultural ecosystems, and recently in vineyards.

[7][6] The female Badumna longinqua spider can potentially spend the whole of her life in the one same web,[3][14] whereas the sexually mature male is forced to leave his home when it becomes time to reproduce.

[11][3][12][8] From this tubular entrance, it builds a multitude of ladder-like webs in a radiating fashion,[10][18][19] and for this reason it is placed into the ladderweb spiders grouping, of which it is one of only a few in New Zealand.

[11][4][12][2][3][19] Despite possibly being one of the most abundant spiders around homes and buildings throughout New Zealand,[4] B. longinqua itself is not often sighted as it feeds at night and will stay hidden in its retreat during the daytime.

[7][2][8] Victims that make the fatal mistake of blundering into the sticky web are rushed at, bitten, and further entangled by the spider until unable to move or escape.

[7][4][12] If this prey is caught during the day, the grey house spider retires back into the safety of its burrow, to emerge after nightfall and feast on its earlier catch.