## 4 Results
### Thermal Response under Free-Floating Temperature Conditions  
As a result of the monitoring period under free-floating temperature conditions, a positive effect on the temperature regulation capacity of the test cell was observed thanks to the incorporation of PCM-based mortars into internal coating elements. This effect was observed for both the PCMs utilized in this work: Micronal(r) DS 5001 X ('Micronal' in the following) and CrodaTherm(tm) ME 29P ('CrodaTherm' in the following). However, some quantitative differences can be described as derived from the monitored data. Next, the results obtained for the two different materials are presented, including a statistical overview per month of the room air temperature values along with the whole monitoring campaign, as well as a specific zoom on the thermal behavior observed during three consecutive, representative days on free-floating temperature mode operation. In both cases, a comparison between the reference cell, DEMO1 (only using WEDI panels without PCM), and the test cell equipped with the PCM-based mortar, DEMO2, is discussed. Figures 7 and 8 show the effects derived from Micronal tests. In addition, it can be observed that the separation of the reference and the PCM-related room temperature curves occurred at thermal levels very close to the phase change range of the material (21-24.1 \({}^{\circ}\)C). Slight differences were reasonable since the room air temperature (monitored variable) and the mortar temperature (actually driving the phase change process) were not expected to coincide due to indoor-outdoor temperature differences and the corresponding thermal resistance. Figures 9 and 10 show the effects derived from CrodaTherm tests. Figure 8: Comparison of room air temperature values at DEMO1 (reference cell without PCM) and DEMO 2 (test cell incorporating Micronal-based panels). Zoom on three consecutive days on the last week of June 2021. In light green, the room temperature difference between both cells is shown. Figure 7: Statistical analysis per month for the comparison of indoor room temperature values monitored at DEMO1 (reference) and DEMO2 (test cell) during free-floating temperature mode periods with indoor coating elements based on Micronal® DS 5001X. From the statistical analysis of room temperature measurements for the reference cell (DEMO1) and the test cell with CrodaTherm-based internal coating (DEMO2) along with the whole monitoring campaign (Figure 9), a clear reduction of the indoor temperature fluctuations during summer and shoulder seasons (from March to October) was observed. Maximum indoor temperatures in DEMO2 were in general 1-2 \({}^{\circ}\)C lower than those in DEMO1. Similar to previous observations for Micronal PCM, due to the operating temperature range of the CrodaTherm PCM, during the winter season (e.g., January and February), no indoor temperature benefits from the PCM-containing mortar were noticed. Figure 10: Comparison of room air temperature values at DEMO1 (reference cell without PCM) and DEMO 2 (test cell incorporating CrodaTherm-based panels). Zoom on three consecutive days on the 2 nd week of April 2021. In light green, the room temperature difference between both cells is shown. Figure 9: Statistical analysis per month for the comparison of indoor room temperature values monitored at DEMO1 (reference) and DEMO2 (test cell) during free-floating temperature mode periods with indoor coating elements based on CrodaThermTM ME29P. In addition, the impact of using the PCM-based mortar with CrodaTherm as indoor wall coating of DEMO2 on the passive thermal regulation of indoor temperature is highlighted when zooming into those weeks with extreme indoor temperatures.