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buildings. However, different occupational rates, thermal comfort and global warming potential of
these kind of buildings have not been covered by the national literature, which proves the
originality and actuality of the present paper.
In this context, the aim of this study was to evaluate the relation between different classroom
occupational densities, energy consumption and global warming potential, by accounting the CO
2eq
emissions during the life cycle of a school building, located in Goiânia – GO.
2. METHODOLOGY
Applying a complete Life Cycle Assessment (LCA) to buildings is a complex task because of the
long life cycle, different involved phases (construction, operation, maintenance and end-of-life) of
the buildings and many environmental impacts such as acidification, global warming potential,
eutrophication, abiotic depletion and others (SILVESTRE; BRITO; PINHEIRO, 2014). Therefore, in
this study, only the global warming potential, in terms of equivalent carbon dioxide (CO
2eq
), was
evaluated. Three phases of the building life cycle were considered: construction, operation and
maintenance.
The functional unit for this study is a school building located in Goiânia – GO, with an internal floor
area of 987.6 m² with a 50 years lifespan (minimum value according to the ABNT NBR 15575-
1:2013), resulting in “50 years school”. The ceramic brick building is composed of two floors,
twelve classrooms, four lavatories and circulation areas. The same building, presented in Figure 1,
was already studied by Paulse et al. (2016).
Figure 1.
(A) Scholar building evaluated; (B) Frontal façade.
Source: Pause et al.
(2016)
For building materials, in construction and maintenance phase, were adopted CO
2eq
factors from
the literature, taken from Saade et al. (2014), Souza et al. (2016) and the environmental product
declaration (EPD) of Votorantim Cimentos (2016). During the maintenance of the building,
replacement factors were adopted (when building materials were replaced) according to NBR
15575-1 (ABNT, 2013) at level M (minimum). The transport distance of building materials was
considered to be 100 km from factories to building’s site.
As one of the objectives of this study is to evaluate the relation between different occupational
rates, energy consumption and global warming potential, three different numbers of occupants in
classrooms (48 m²), with 20, 30 and 40 students were adopted, resulting in three occupational
rates: 0.42 student/m², 0.63 student/m² and 0.83 student/m², respectively. For the thermo energetic
simulation the Design Builder software with Energy Plus was used (Figure 2).