## 4 Evaluation of the Cost Prospects of the Implementation of Utility Functions  
The building subject to measurement is intended for permanent human occupancy as a residential building. It is located in a new housing estate of single-family houses, primarily occupied by young families. An analysis of requests for social infrastructure within the 3-hectare area in the suburbs of Krakow, developed with single-family residential buildings, identified the following three utility functions for the house, which appear to be the most socially and economically justified:  
* Variant V1--nursery and kindergarten;
* Variant V2--shop;
* Variant V3--office. The base residential function was labeled as Variant V0. The suitability of the investigated building for each of the proposed utility functions was analyzed according to the following criteria:  
* F1: Thermal comfort expressed in terms of operative temperature in winter (class A (20 \(<\) to \(\leq\) 21), class B (19 \(<\) to \(\leq\) 20), and class C (18 \(<\) to \(\leq\) 19))
* F2: Percentage reduction in building airtightness envelope n50 (increase in building envelope airtightness) [1/h] (class A (0 \(\leq\) n50 \(\leq\) 0.6), class B (0.6 \(<\) n50 \(\leq\) 1.5), and class C (1.5 \(<\) n50 \(\leq\) 3.0))
* F3: Non-renewable primary energy indicator EP [kWh/(m2 year)] (class A (0 \(\leq\) EP \(\leq\) 42), class B (42 \(<\) EP \(\leq\) 56), and class C (56 \(<\) EP \(\leq\) 70))
* F4: Vibrations in HPVR (class A, class B, and class C). Table 7 summarizes the measurement data for the specified criteria for the current state of the building. Table 8 shows standards of all criteria that the building must meet in the case of the implementation of each of the utility functions. The current construction phase of the building under study was compared with the standard requirements for the proposed utility functions V0-V3, indicating the required and available class for each of the four criteria F1-F4, as presented in Table 9. \begin{table}
\begin{tabular}{l l l} \hline \hline
**Criteria** & **Measurement Data** & **Compliance Class** \\ \hline F1 Thermal comfort & 21.03 \({}^{\circ}\)C & A \\ \hline F2 Airtightness of the building envelope & 574.16 m3/h & C \\  & 1.64 1/h & C \\ \hline F3 Non-renewable primary energy indicator EP & 68.65 kWh/(m2 rok) & C \\ \hline F4 Vibrations in HPVR & WODL-factor 2.75 & C \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Summary of measurements. \begin{table}
\begin{tabular}{l l l l l} \hline \hline  & **Variant V0—Base** & **V1—Nursery and** & **Variant V2—Shop** & **Variant V3—Office** \\  & **Residention** & **Kindergarten** & & \\ \hline F1 & 21—class A & 21—class A & 20—class B & 20—class B \\ \hline F2 & 0.6—class A & 0.6—class A & 3.0—class C & 1.5—class B \\ \hline F3 & 70—class C & 42—class A & 56—class B & 56—class B \\ \hline F4 & 2.0—class B & 0.9—class A & 4.0—class C & 4.0—class C \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Requirements for variants and classes of building. As shown in Table 8, there are three possible relationships between the required class for a certain criterion and the actual class determined based on the measurement results for the building in its current state. These are as follows:  
* The class required by the standards is higher than the current class (indicated in bold). * The class required by the standards matches the current class (marked with a pink background). * The current class exceeds the requirements of the standards (indicated by a blue background). The estimation of capital investments needed to improve the building's condition for each proposed utility function assumes an increase in the class of each criterion by one point (e.g., from B to A) for a conditional cost unit of 1 c.c.o. The required expenditures for each utility function are as follows:  
* Variant V0--base residence: Requires improving criterion F4 by one point (from C to B) and criterion F2 by two points (from C to A):  
M(V0) = 1(F4) + 2(F2) = 3 c.c.o.