I believe, descended
Victor's workshop, he reported earlier (1.3.6), was a cell at the top of the
house, separated in a complex way from the main part of the edifice.
Presumably, the bedchamber to which he fled at the awakening of the
Creature (1.4.2) was on a floor below.
There the Creature wandered and awoke Victor who then in terror plunged
outside. By some means unknown to Victor and unremembered by the
Creature, the newly created being made his way from the house to the
streets outside the courtyard, where Victor spent the night, and thence
into the countryside surrounding Ingolstadt, where at last he fell