The present study deals with the urban apartment houses in the historical center of Thessaloniki and their development up to day. After field research, characteristic examples of every period were selected, and their building permits sought out in city planning archives. Information was gathered, by which the buildings were categorized, and they are presented according to their year of construction. With parallel historical research on the period of the apartment houses’ construction, regarding the social, economic and legislative framework, a complete approach to the development of this dominating model of built environment production is attempted.

Concerning the socio-economic framework, the urban apartment house appears in Thessaloniki after the fire of 1917, as a solution to the dwelling problem, and as a form of innovation.

Legislatively, the way to the apartment house opens with the settlement of the horizontal property issue (Law 3741/29). The regime of ownership changes, as, where initially every structure belonged to the landowner, after 1929, different parts of the structure can belong to different owners.

The urban apartment house followed a course of commercialization, based on private funds, from 1920 to date. The funding of the urban apartment houses’ production process varied, with the final owner financing it exclusively, or him asking the participation of other physical persons as financiers or contractors. Also popular, especially after World War II, was the process of “giving in return”.

Correspondingly, the construction could be carried out with supervision by the land owner or the supervising engineer, as well as with contract work. The construction-teams worked by task work, i.e. with wage per construction project. The potential offered by construction technology, reinforced concrete, and the domestic construction industry, played a key role in the development of multi-storey buildings in Greece.

The first legislation regarding building regulations is enacted for the redesign of Thessaloniki, in 1918. Law 1394/18 becomes the basic instrument for the redesign of the city. The new plan was assigned to French architect and urbanist E. Hebrard. The laws of 1920, 1921, and 1922, concern themselves about building permits, urban systems, maximum heights, clear spaces, elevations, and the conditions under which construction works are carried out.

During the period 1920-1929, a tendency for the entire plot being covered by the building is observed. Morphologically, layouts with central or sidelong axes of symmetry, base-shaft-capital arrangements, oriel windows up to 1.20 m depth, and crowning by cupolas, prevail. Special care is taken for corner formation. The prevailing styles are Eclecticism and Art-Nouveau. Typologically, the apartment’s organization is based on a core, around which are deployed, with strict hierarchy: reception, resting, and food preparation spaces. So, we have an absence of separation of the main functional modules, and immediate communication between the partial spaces. Also during this period, the concept of common spaces (common storage spaces and laundries), and the janitor’s/caretaker’s profession are introduced. Closing, the absence of elevators and comfortable staircases encumber vertical communication.

With the General Building Regulation (G.B.R.) of the period 1929-1955, the building legislation becomes systemized. Innovations are to be found in sanitary and safety issues, urban systems, the building’s appearance, and settlement of the building plots. This period’s apartments target mainly the lower middle-class. Morphologically, architects turn towards the decorative vocabulary of Art Deco. Geometric shapes, linear frames, bright colors, stylized decorations, shaped ends, and bas-reliefs dominate the facades. Typologically, a nodal space emerges in immediate communication with the entrance, which divides the apartment in two, and later three spatial modules (reception, resting, food preparation). These modules are connected in different manners, which seem to be preferred by different socio-economic classes. Vertical communication is now accommodated by elevators.

The period 1955-1973 is a historically and socially troubled one (World War II, German Occupation, Civil War, Military Dictatorship, intense urban attraction). With the G.B.R. enactment of 1955, the apartment house’s typology, standards and “technology” become established. Goal is the utmost exploitation of urban property and the enforcement of technical specifications. The intense exploitation of the building plots led to high densities, excessive heights with regard to street width, and shrinkage of the presumable free spaces surrounding the monuments. Morphologically, the facades are shaped solely by the repetition pattern of the openings, the continuities and discontinuities between balconies, the display or coverage of the bearing structure, and the visible masonries and facings. The oriel windows become smaller (0.40 m), and the pilotis appear. Typologically, the bigger – more expensive apartments are located on the upper, and the smaller – cheaper ones on the lower floors. The bearing structure’s layout is random. The apartments are organized in three zones: a bright one towards the street (reception), a dark one in the centre (common spaces) and another bright one towards the backyard (resting). Reception spaces grow larger against the other rooms. The light well is introduced, and the “typical floor” gets circumvent.

The G.B.R. of 1973 focuses on standardization, on the subordination of the building to the building plot, and the check of the building plot against minimum lot requirements. As a result, the concept of the Floor Area Ratio (FAR), or Floor Space Index (FSI), is established, the construction of parking places emerges, and the property’s contribution in land and money for the reservation of land for communal spaces is enforced. Immediately, the design of buildings and open spaces becomes subject to impersonal regulations of general validity. The product, the apartment house, essentially doesn’t change in appearance, in regard to the previous period. Accordingly, neither the typological pattern of the apartments, nor their internal functional organization change. As of the structure’s placement on the building plot, contact with the boundary, or a minimum distance of 2.5 m are imposed. Moreover, minimum dimensions for clear spaces are specified.

The G.B.R. of 1985 introduces the architect’s (as well as the owner’s and the contractor’s) “freedom”, as to the building’s volumetry and placement in its immediate and greater surrounding area. Institutions like the “Active Building Block” and the Unification of Open Spaces, the building’s use and the Committees for Architectural and Urban Control are created.

Today, the urban space of Thessaloniki is disconnected from its architecture. The excessive exploitation’s and overdevelopment’s consequences can be seen in the rising of urban land prices, and in the high densities of built mass and inhabitants. The results are the unhygienic conditions, the disappearance of green, sunlight and view, as well as the low living quality in this city.