In buildings with a reinforced concrete (r.c.) skeleton structural system, components of the structural system like, beams, columns or cantilevered slabs in the external envelope mostly break the continuity of the thermal insulation layer or the self-insulated wall, causing "thermal bridges". In addition junctions between the exterior wall and other building elements like other walls, roofs, slabs, windows or doors are creating areas where the heat transfer is higher than a part of a wall free from thermal anomalies. Such "thermal bridges" not only increase heat transfer but also are potential cold surfaces for moisture accumulation. Different architectural details for the intersection of building elements and the structural system are resulting in different thermal performance. In this context, the intersection of the "exterior wall / slab-on-grade" area is studied, considering the heat flow through the combined construction. Buildings without a basement are taken into consideration. Various architectural details in different constructions are analysed and evaluated. Alternative wall and slab-on-grade constructions with and without thermal insulation are considered. In the analysis, the selected materials for construction of walls and slabs, placement of the thermal insulation are utilised as variables. The thermal performance is determined with the PC-program "HEAT 3". The program works with a transient or steady-state, three dimensional, finite difference model for the heat transfer. The thermal performance of different "exterior wall / slab-on-grade" combinations are given as a result of the study. The thermal performance of architectural details for this coupling area, using common construction types and typical building materials for residential buildings in Turkey, are also compared with the "regulatory" values.
