In active systems, both liquid and air, the following elements can be distinguished:
- collector system (outer part;,
- transport system, controlling, emitting energy (inner part),
- hopper (warehouse) thermal energy (inner part).
From the architectural point of view, it is possible to completely separate the installation of the active system from the building structure and only the heat emitters would have to be located inside the building.
However, individual solutions are the most common, in which the system of collectors with the required area of 30 do 90 m2. The most effective inclination angle of the collectors in relation to the horizontal for year-round heating is equal to the latitude ±10°. Solutions are found, where the collectors are not integrated with the roof structure (building).
More often though, for practical and economic reasons, collectors are placed in the roof slope, which makes it possible to use them as surfaces protecting against precipitation and thermally insulating the attic space.
Active systems do not force a new way of designing a single-family house, which often in its external form does not differ from traditional houses. The only distinguishing feature is the replacement of roofing materials with solar collectors in the slope facing south (Fig.2). Often, however, such a conservative attitude of the architect leads to inappropriate effects, for example, for multiple refraction of roof slopes (Fig.3), or excessive protrusion of the roof slope beyond the outline of the building due to the need to accommodate large-area collectors (Fig.3).
Before starting conceptual work, the architect should know the basic assumptions regarding the designed active system, which can significantly affect the solution of the building.
The issue of the possibility of obtaining the maximum area for installing solar collectors, as a function of the shape of the building, can be considered for various forms of single-family buildings. The analyzes show, that the forms of "solar architecture" (Fig.4) have at least twice as much space for solar collectors, than traditional forms with similar volume and external surface.