## 4 Results and Discussion
### Living Conditions as an Expression of Retrofit Requirements  
Respondents' current living conditions can be indirectly assessed when asking for the requirements to implement specific home retrofits regarding the three dimensions discussed in the methodological section, as well as, in the case of retrofit necessity, the relative priority to implement such improvements. To some extent, the current living conditions may exert a role in the perception of energy-performance co-benefits, especially in the case of people whose residential environment alternatively implies high energy consumption to reach a proper comfort level, or a poor comfort level to reach an affordable energy consumption. Past research, in Spain, has identified a relationship between poor/adequate energy-related living conditions and willingness to pay for energy-efficient homes [6]. Figure 5: Perceived co-benefits according to respondents’ sociodemographic profile. Source: Self elaboration. In this paper we go a step further to learn whether such conditions do affect the perceived co-benefits of energy performance. As said before, 88% of respondents' homes do require to be improved in the assessed aspects. However, if such retrofits are split, relevant differences emerge: 90% of homes require a retrofit associated to passive energy-efficient actions (e.g., building envelope insulation), the figure is reduced to 86% in the case of active energy-efficient improvements (e.g., HVAC); while 88% of respondents require non-energy efficient improvements (e.g., kitchens) to be evaluated. Such findings are related with the fact that in the context of multifamily homes, which is dominant in Spain, implementing passive improvements is significantly more complex due to the communal nature of building envelope elements, comparing to improving private spaces such as bathrooms and kitchens or replacing individual boilers. For these reasons these latter retrofits are more popular than others effecting the energy performance. Thus, the gap of such passive-energy conditions is larger than those related to private elements. Figure 6 illustrates the percentage of homes requiring a specific retrofit as well as the percentage who felt it necessary to prioritize implementation; the information is split according to respondents' sociodemographic profile. From this, the following conclusions can be highlighted:  
\begin{tabular}{l c c c c c c c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**Homes not requiring retrofits**} & \multicolumn{3}{c}{**Average priority for retrofits**} & \\ \multicolumn{3}{c}{**Agp**} & \multicolumn{3}{c}{**Agp**} & \multicolumn{3}{c}{**App**} & \multicolumn{3}{c}{**App**} & \multicolumn{3}{c}{**App**} & \multicolumn{3}{c}{**App**} & \multicolumn{3}{c}{**App**} & \multicolumn{3}{c}{**St Dev**} & \multicolumn{3}{c}{**Avg**} & \multicolumn{3}{c}{**St Dev**} & \multicolumn{3}{c}{**Avg**} \\  & **18-24** & **25-34** & **35-45** & **55 and more** & & & & & & & & & & & & & & & & & & & & \\  
Findings Regarding Respondents' Age
1. In general, the older the respondents, the lower the requirement to implement specific retrofits in their current home. Such a finding suggests that living conditions improve as the residential carrier gains consolidation, although it also possibly masks some conformism regarding living conditions in the case of elder population. However, the requirement to improve envelope insulation (walls and windows) is largely irrespectively of the age of respondents. 2. Looking at homes requiring improvements, non-energy efficiency improvements, such as kitchen, bathroom or layout improvements, are less of a priority as the age of respondents' increases. Interestingly, the exact inverse trend is observed in the case of window insulation which relevance becomes larger in the case of older respondents. Findings Regarding Respondents' Gender
3. In general, women's homes require less improvements than male respondents' ones, thus female respondents exhibit better living conditions in relation to male respondents.