The phenomenon of decentralization of inhabitancy directed beyond the limits of spatial structures qualified as urban, occur most of all among middle class (which constitutes the majority in group of building investors). We may simply talk about the increasing tendency of flowing people from this class to the outskirts of the city. In an author's opinion contrary to the expressions in thesis, the reason for that, beside an economic benefits is: searching for safety, individualization of surrounding area, and the humanization of friendly, neighbourly relations. Within the reach of a formally urban structures emerge dwelling-houses of a character close to a rural architecture. This phenomenon is an evident appearance of their inhabitants needs. In this context we ought to oppose the attempt of antagonizm in valuation as to refer to urban and rural structures. The state of space on the vast areas within the administrative urban borders we can define as penetration and mesh of rural and urban structures.lt seems to be necessary to introduce and ratificate in terminology and in planning and architectural practice the definition of the „bordering zone", as adequate to that spatial situation. The quality of that space is essential and it is stated in thesis as order. To be in search of that order, which formal features are in the author's opinion identical for any spatial structure either urban or rural is an actual necessity. In the report author produces the list of such features treating it flexibly as open.