The GO5 Terraces Waterproofing project consisted of restoration of existing waterproofing for 41,300 SF surfaces located on the tri-level terraces on the 2nd, 3rd, and 4th floor of the Southern California Edison General office in Rosemead, CA. The elastomeric coating was beginning to delaminate causing moisture penetration risk below the topping slab on the decks and stairs and bypassing to the coal tar pitch membrane and structural slab.  The project required the demolition of the removal of the existing elastomeric coating down to the structural concrete and installation of new concrete topping slab with application of new waterproofing membrane system including new sheet metal, sealants, and Electric Field Vector Mapping (EFVM).