*3.8.2 Total costs VUF and VAC*

From a common architectural design, the structural plans were developed and from which the metrics were measured and from which the housing costs were established, according to each type of housing designed, that is, 12 budgets were developed, with which the comparative analysis is carried out. By the comparative method, the principle of homogeneity and similarity was taken into account in order to make a comparison according to the proposed methodological design.

The design of items and costs of both building processes was developed from the same architectural design, expressed in a production line and trying to avoid falling into a comparative analysis of efficiencies, an aspect that is not considered in the research project. As a result of this process, the costs of the VUF and VAC singlefamily houses are presented (**Tables 13** and **14**).

Carrying out a conceptual contrast of the building processes by VUF precast elements in comparison with the construction processes by confined VAC masonry, the building with precast concrete elements exceeds in the reduction of time and costs, which has been reconfirmed in the calculations made (**Figure 15**).

According to the graphical representation of the costs of the VUF and the VAC, the cost difference is notable having the lower cost of the houses built with precast


#### **Table 13.**

*Costs in suns and dollars of one (VUF).*


#### **Table 14.**

*Costs in suns and dollars of an VAC.*

**Figure 15.** *Linear Total cost of VUF and VAC.*

VUF concrete elements. The relation of total costs and surfaces for building processes, presents the following trend.

For VUF, a linear trend of y = 364.91x + 1219.2 (R2 = 0.9906) is presented. This trend is very low compared to the VAC trend. Which shows that the VUF building costs are below the costs of a confined masonry building process.

For VAC, there is a linear trend of y = 563.85x + 301.69 and (R2 = 0.9799) this trend is very high compared to the VUF trend. Which implies that VAC costs are high compared to VUF costs (**Figure 16**).

**Figure 16.** *Projected trend lines of cost/surface of VUF and VAC.*

*Low-Cost Single-Family House through The Use of Precast Reinforced Concrete Elements DOI: http://dx.doi.org/10.5772/intechopen.98430*

The projected trend of a VAC confined masonry building process exists a direct relationship and is determined by a coefficient of 0.9799 between cost in dollars and housing surface, which implies that the greater the built surface, the greater the investment and the slope of growth are required. is high. The trend of a VAC process significantly exceeds in costs a building process with VUF prefabricated elements, which allows confirming the efficiency of the VUF building process.
