# Monitoring a Pre-Normative Multi-Family Housing Case-Study in a Mediterranean Climate
## 3 Methodology  
The case-study dwellings have undergone an energy assessment according to the methodology carried out in similar work of the research group TEP-130 of the University of Seville [29]. The objective of the monitoring campaign is to register environmental indoor data in order to carry out an analysis to observe how indoor measured parameters unfold over time. The monitoring period began on 1 April 2013 and finished on 31 March 2014. A daily data record was made at 30-min intervals, resulting in a total of 563,328 entries. Monitoring was undertaken following the ISO 7726:1998 protocol [30]. This international rule both specifies the minimum requirements of the use of instruments to measure physical parameters related to environmental conditions and explains the measurement methods. The main aim of this set of regulations is not the determination of a global comfort index, but the standardization of the registration process of environmental data that can be later used to determine these values. Data registration was performed using four data loggers (Figure 5). One of these loggers is named the master, and it is in charge of the weather station located outdoors. The devices have a memory capacity of 75 days; therefore, data have to be periodically transferred to a laptop by USB connection. On the application of the Easy Weather program (a communications and monitoring software tool), data are readily translated into a tabulated text format, in order to ease data treatment using a data processor software tool (Microsoft Excel v. 2013). Data loggers may be manipulated by a touch-screen or by using the Easy Weather software tool. Amongst the different variables registered indoors, air temperature and relative humidity have been recorded by means of two separate sounding lines located in the living-room (day zone) and in the bedroom (night zone) in each dwelling. A weather station located on the outdoor balcony completes the whole system. The weather station is protected from solar radiation and is south oriented (Figure 6) (Table 2). Outdoor air temperature, relative humidity, wind direction and speed are registered with this device. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Devices** & **Weather** & **Bedroom** & **Living-Room** & **Bedroom** & **Living-Room** \\
**(Indoor/Outdoor)** & **Station** & **Dwelling A** & **Dwelling A** & **Dwelling B** & **Dwelling B** \\ \hline Air temperature & 1 & 1 & 1 & 1 & 1 \\ Wind speed and direction & 1 & 0 & 0 & 0 & 0 \\ Relative humidity & 1 & 1 & 1 & 1 & 1 \\ Total & 3 & 2 & 2 & 2 & 2 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Summary of installed devices in the monitored dwellings. Figure 5: Distribution of the monitoring devices. A pressurization and depressurization test has been carried out in the monitored dwellings in order to complement the analysis of the results obtained. Air-tightness has been measured using blower-door equipment, in accordance with the ISO 9972:2015 protocol [31]. Additionally, a thermography analysis of the building envelope has also been carried out, with the aim of identifying air-leak points and thermal bridges and to ascertain the level of thermal homogeneity that the external walls offer. From the pictures in Figure 7, the fairly weak points concerning thermal losses can be observed in the upper part of the window where a blind box is located, which acts as a highly ventilated air chamber. Clear differences of temperature of the blind box and the window surroundings can clearly be determined from the indoor thermography. This blind box can easily be identified from outdoors, as well as the framework's edge, both therefore indicating a thermal bridge (Figure 7). Table 3 offers infiltration rates in the two dwellings at 50 Pa pressure, as well as its estimation in atmospheric pressure. Global results for the whole monitored housing units offer a value of 0.36 air change per hour (ACH) in Dwelling A and a 0.48 ACH in Dwelling B, which are fairly high levels of air-tightness.