The restoration of the Müller Villa was preceded by expert surveys (a structural historical survey, an architectural survey, and a survey of the physical state of the building and its fittings). These major research undertakings uncovered many new, hitherto unknown facts, and it was thanks to them that all of the available historical photo documentation, original sketches, drawings and plans of the house by Adolf Loos and Karel Lhota were brought together.
The surveys confirmed that despite its varied fate after 1948, and the neglect it had suffered, the building had survived, relatively speaking, in a very satisfactory structural/technical condition. Its basic structure was sound, and no major structural or technical interventions had been made. The state of the structure and the materials was proportional to the length of time that the house had existed. The inner, spatial organization of the house had been preserved almost entirely as it was originally envisaged. Most of the structural parts of the building (including an almost complete set of fundamental, authentic structural elements and materials) as well as most of the original fittings (floors, fitted furniture, claddings, wallpapers, light fittings and bathroom fittings, including collections of metalwork details, switches etc.) had been preserved. The original, and today almost uniquely preserved, technical fittings and equipment (kitchen fittings, elevators, central heating with the original boiler installation etc,) remained, along with a whole range of minor furnishings from the original interiors. Original doors and windows also survived in their original locations, although sometimes damaged and in most cases with non-original finishes. To a great extent, the original ceramic, xyolite and concrete floors, as well as the terra alba, gypsum plaster, stucco and cement interior plasters, also survived. Stone, wooden (veneered or varnished) and glass claddings remained in situ as well, as did wallpapers (either paper or natural fiber) and cladding materials such as matting and linoleum. The fitted furniture remained in generally good condition with only slight damage (in the hall and cloakroom, the living room, the dining room, the library, Mrs. Müllerová’s bedroom and the kitchen). The existence of a unique collection of original sanitary system elements – an English washbasin, a water closet, a bowl with the original lead piping, nickel armature, taps and a range of complementary objects (such as shelves, mirror, bracket and towel rack) – was exceptional. Despite its varied fortunes, the building still contained a large number of the original 1930s light fittings, too. A set of original switches, plugs and signal bells also remained intact, while the central heating circulation system with its cast iron radiators survived almost in its entirety.