Embodiments of the invention include interconnect layers with floating interconnect lines and methods of forming such interconnect layers. In an embodiment, a plurality of openings are formed in a first sacrificial material layer. Conductive vias and dielectric pillars may be formed in the openings. A second sacrificial material layer may then be formed over the pillars, the vias, and the first sacrificial material layer. In an embodiment, a permeable etchstop layer is formed over a top surface of the second sacrificial layer. Embodiments then include forming an interconnect line in the second sacrificial material layer. In an embodiment, the first and second sacrificial material layers are removed through the permeable etchstop layer after the interconnect line has been formed. According to an embodiment, the permeable etchstop layer may then be stuffed with a fill material in order to harden the permeable etchstop layer.