The aim of this paper is to show a thorough example of what is currently known as the "urban revolution" of Ostia between the 1st and the 2nd century AD, where large areas of the city, previously occupied by one-storey houses and small buildings, where destroyed to give space to the large, efficient and multi-storeyed commercial and residential buildings, the sc. insulae that are so well represented in Ostia antica. This phenomenon has until now been studied as a general urban phenomenon. Our aim is to shift from the macro-urban scale to the micro-scale of a single parcel of land, named IV, VI 1 in the Topografia generale of the Scavi di Ostia collection. In this area, located between the forum and the Porta Marina, along the decumanus maximus, a rich residential house, the Domus del Portico di Tufo, is destroyed and replaced in the first years of the 2nd century by a multi-storeyed residential building, the Caseggiato a Botteghe. The "Ostia ReLOADed" excavation project, carried out since 2019 by the belgian universities of Louvain and Namur, has allowed to give an in-depth view of the building processes that lead from the domus to the insula. We will show that, even if the two buildings are completely different in status, function and appearance, many walls of the latter building are in fact reused from the earlier one. We will therefore enlighten a rarely approached phenomenon: reuse and recycling of plans and structures in the 2nd century building sites.