## 3 Results and Discussion
In apartment A5, on the contrary, a constant window opening was applied during the day, keeping one window half-open during the night. Rollers were drawn down but not closed. This dwelling had the highest internal gains because of a small area, long TV and computer usage, and an electric water boiler installed in the bathroom. However, cooking was very rare, and the measures undertaken helped to lower the overheating time to 8.1% of the monitoring period. Opposite the dwelling, there was a drying room facing south with a long row of windows, which could cause a greenhouse effect and raise the internal temperature there, contributing to the temperature growth in A5. The owner reported the space to be very uncomfortable both during summer and winter. An interesting insight into the thermal conditions in dwellings may give a comparison between temperatures in the sets of flats of identical layouts (A1, A4, A6 and A8, A10). The number of overheating hours in the first set (A1, A4, and A6) in the rooms facing southwest or south equals adequately 163, 62, and 0. The factors contributing to more favourable conditions in dwellings A4 and A6 compared to A1 were:  
* A strictly southern orientation: This may lower the internal temperature, especially in the afternoons, compared with the SSW orientation of the A1 apartment (30\({}^{\circ}\) S of W). The literature on the subject [19; 51] pointed out that a western orientation may cause temperature rises in rooms when solar gains are connected with a higher outer temperature caused by all-day heat accumulation in the ground, buildings, or other external objects. * Location in the middle floors of the buildings: Apartment A1 was additionally heated from the flat roof of a dark grey colour, absorbing solar radiation. The roof was rather poorly insulated, so the insulation layer was not a sufficient obstacle to heat transferring into the building. Previous research has confirmed this trend of higher temperatures in the top floors [32; 35]. * Internal gains in the apartments were not the lowest (11.5 W/m\({}^{2}\) and 9.1 W/m\({}^{2}\)), instead, they did not play a decisive role in the shaping of the internal conditions. * The best measures taken to lower internal temperatures were opening or cracking open windows together with trickle ventilation--measures taken by the occupantsof apartment A6. In apartments A4 and A1, the first action taken in the case of a temperature rise was closing the windows. In A4, part of the windows facing south were shaded during the day, but in A1, the blinds installed in the bedroom were never used. This caused the worst thermal conditions among monitored dwellings. In the second set (A8 and A10), the shading and ventilation patterns were very similar. In the rooms facing south, the shading was hardly or not used, one window was cracked open, and the balcony doors were opened during the day. Worse conditions in apartment A10 could have been caused by the western rotation of the living room and the twice-as-big glazing-to-floor ratio. Considering the rooms facing north, the A8 dwelling was rarely occupied. In the A10 dwelling, the bedroom was lodged by a partly disabled person, spending most of the day there. Despite one window being cracked open constantly, the number of overheating hours was higher than in the corresponding room in A8. Another factor contributing to the poor performance of the A10 dwelling was the higher internal gains connected for two occupants. To compare these results with the personal perception of internal conditions, the occupants of the apartments were asked to evaluate their living environment using the thermal sensation vote (TSV) ASHRAE seven-point scale (-3 cold, -2 cool, -1 slightly cool, 0 neutral, +1 slightly warm, +2 warm, or +3 hot). They were also asked what percentage of monitoring time they would assign on a scale from 0 to +3 (Table 6). When the highest noted temperature was equal to or bigger than 30.0 \({}^{\circ}\)C, the inhabitants assessed their thermal environment as reaching level +3, meaning hot.