The disclosed invention provides a system and method of installing wall panels unto an existing wall. The primary object of the disclosed system is to enable mounting of wall panels or windows on an erected latticework. Such latticework is deployed on exteriors of existing walls or is mounted across floor slabs. The system is comprised of a plurality of parallel upright assemblies stretching from slab of one floor to slab of the next floor. Crossmembers fastened to the parallel upright assemblies serve as mounting points for wall or window paneling.