**4.3 Analysis of the potential for improvement in the PMV and PPD indicators according to the wall variants LAD-MA**

The construction variants are represented below, through a dynamic thermal calculation model developed in the DesignBuilder 6.2 program, using the Energy Plus calculation engine. This representation aims to approach the thermal results obtained empirically in the LAD-MA homes built through a representative digital model of the LAD-MA architectural module. For the analysis, an adiabatic condition was considered for the roof of the module. **Figure 5** shows the model represented.

The analysis is carried out based on the climate of Santiago and focuses on the thermal comfort results of the module and the PPD and PMV indicators for each variant studied. **Table 8** presents the results obtained from these indicators, considering the winter and summer periods and the annual total.

It is observed that the representative thermal model of the original LAD-MA system presents 69.7% of the time in thermal discomfort in the annual period. It should be noted that the discomfort conditions increase when applying stucco on both sides (variant 2). The solution with the greatest impact on reducing annual thermal discomfort is clearly variant 4, consisting of the incorporation of thermal insulation on both sides of the wall, with which the time in thermal discomfort is reduced from 69.7% to 63.3%. It is worth highlighting the positive effect of the thermal insulation solution during the summer period, which reduces the transfer of heat into the home, reducing, in turn, the time in thermal discomfort of 61.1% in the home with the LAD system. -Original MA, at 53.1% when thermal insulation is added on both sides.

### **5. Conclusions**

The study allowed observing the performance and thermal comfort of social housing built 30 years ago, which were designed to respond to urgent needs of habitability of vulnerable families in camps, to provide a basic infrastructure, expandable over time, based on the needs of each family, concluding that they fulfilled the objective for which they were built in their time. It is worth mentioning that in this context, the thermal comfort of the dwellings was a secondary aspect given the various shortcomings and challenges of the beneficiary families, who over time put their economic efforts into expanding and providing new spaces to their dwellings. This is clearly observed in the homes studied, which prioritize new spaces over construction quality and the thermal envelope. However, the study also shows that by building new spaces, the beneficiaries have been undermining the performance of the house, from the point of view of its natural lighting and ventilation.

It is observed that the monitored LAD-MA homes present thermal comfort standards below international standards and that they currently do not meet the thermal envelope requirements for homes in the country. Given the above, constructive solutions with low economic impact were studied, using computational methodologies, which could be progressively implemented in the wall construction system, to comply with local regulations and gradually improve interior comfort conditions. In this case, it is concluded that the incorporation of thermal insulation layers in the original wall is the best alternative to reduce the hours of discomfort
