[Retracted] Case Study of Carbon Emissions from a Building’s Life Cycle Based on BIM and Ecotect

Table 2

The data of unit energy consumption and unit CO₂ emissions generated by the main building material production.

Number	Main building materials	Unit	Unit energy consumption (kJ/unit)	Unit CO2 emissions (kg/unit)
1	Concrete	Kg	1247.74	0.2420
2	Brick	Kg	2000	0.2
3	Cement	Kg	4464	0.894
4	Lime	Kg	4644	1.2
5	Mortar	Kg	3972	0.792
6	Gravel	Kg	23.8	0.002
7	Stone	Kg	12943	2.33
8	Steel	Kg	33906	2.208
9	Ceramic tile	Kg	15400	1.4
10	Paint	Kg	5837	0.89
11	Glass	Kg	16000	1.4
12	Wood	Kg	1800	0.2
13	Organic material	Kg	90353	17.07
14	Aluminum	Kg	12964	1.407
15	Copper	Kg	23579	1.01

Note: (a) the metal has already been considered for recycling. (b) From a life-cycle perspective, the renewability of the building material must be considered when calculating building material consumption and CO₂ emissions. The building materials associated with renewability include reinforced steel, steel, architectural glass, aluminum extrusion, and wood. Although architectural glass and wood can be totally or partially recycled, recycled glass generally cannot be used again for construction. Wood also cannot be used directly in construction without further processing. Therefore, there is no need to consider the recycling and reuse of glass and wood.