plumbing rough-in services Plumbing rough-in is the portion of construction where the supply and waste lines for the building go into place. In homes with slab foundations, the rough-in occurs before contractors pour in the slab. Typically, waste lines go in first because the pipes that take wastewater from the building are larger than supply lines. After installing the waste lines, the plumbers will then lay in the water supply piping. For more information please click here : https://www.plumbingconcepts.c....om/all-about-plumbin .