This paper presents an algorithm that calculates the radiative view factors based on Stokes’ theorem. The authors propose a formulation where the original surfaces are divided into a grid of elementary areas and Stokes’ theorem is applied for the determination of the view factors between these elementary areas. With this approach, the account of the shading effect of obstructions is significantly improved. The capabilities of the proposed formulation were tested with the calculation of radiative view factors between flat and curved surfaces. The results obtained showed a good agreement with the corresponding analytical solutions, with relative errors (REs) lower than 2%. The proposed methodology was also compared with the application of the double integral area formulation and a better agreement was found, between RE and the CPU, using the present formulation.

Among the aspects with major impacts on the energy and environmental performance of a building, the thermal insulation of the opaque elements of its envelope stands out. This work assesses the influence of the application of thermal insulation to the opaque elements of the building’s envelope on the thermal comfort conditions indoors; moreover, the influence of the thermal insulation on the energy, environmental, and economic costs over the building’s complete life cycle is evaluated. For this purpose, the three most commonly used thermal insulating materials (expanded polystyrene—EPS, extruded polystyrene—XPS, and mineral wool—MW), thicknesses between 0 (without insulation) and 40 cm, five climates (hot, warm, moderate, cold, and very cold), and six types of use (apartment, housing, clinic, school, bank branch, and supermarket) were considered. EPS reveals itself to be the most promising thermal insulation material, both in economic and environmental terms, so it was selected for this study. The EPS’ optimal thickness depends on the building’s type of use, the climate, and the perspective from which the assessment is carried out (energy, environmental, or economic). The results show that the economically optimal thicknesses of thermal insulation are significantly lower than the corresponding ones in environmental terms. Furthermore, the application of thermal insulation to the opaque building’s envelope is more beneficial in energy and environmental terms than from an economic perspective.