INGENIEUR
Major Construction Materials
1 . Steel Reinforcement 2 . Ready Mixed Concrete 3 . Plywood 4 . Bricks 5 . Paint 6 . Sand ( finishes ) 7 . Glass 8 . Cement ( finishes ) 9 . Ceramic Tiles
Table 2 : Selected major and non-major construction materials
Non-Major Construction Materials
1 . Aggregate 2 . Roofing Tiles / Sheet 3 . Steel and Metal 4 . Timber 5 . Sanitary Ware
Construction Material CIDB
Composition (%)
Survey ( this study )
Difference
Steel Reinforcement 3 % 2 % 1 % Ready Mixed Concrete 61 % 55 % 6 % Cement ( finishes ) 2 % 2 % 0 % Bricks 9 % 7 % 2 % Table 3 : Comparison of the average material demand composition with survey results under this study
For GHG emission accounting and quantification , this study adopted the calculationbased approach , which is the most commonly adopted method of accounting for GHG emissions . According to the 2006 Intergovernmental Panel on Climate Change ( IPCC ) Guidelines for National Greenhouse Gas Inventories , the most common simple methodological approach is to combine information on the extent to which human activity takes place ( called activity data or AD ) with coefficients that quantify the emissions or removals per unit activity ( called emission factors or EF ). The basic equation is thus ( IPCC , 2007 ):
Emissions = Activity Data • Emission Factors
Based on the emissions sources identified , AD was collected from relevant data suppliers and respective emissions factors were applied accordingly to calculate GHG emissions . As mentioned earlier , a survey on actual construction projects completed in Malaysia was also carried out to provide further verification and support to the activity data and assumptions used .
GHG Emissions for Construction Industry Value Chain
This study focused on the GHGs which are converted into carbon dioxide equivalent ( tCO2eq .) as covered by the Kyoto Protocol . GHGs covered in this study include the following three types of gases , namely carbon dioxide ( CO 2
), methane
( CH 4 ), and nitrous oxide ( N 2
O ) which have been found to have a direct impact on global warming ( United Nations , 1997 ).
Total GHG Emissions ( Cradle-to-Site ) The average total GHG emissions from cradleto-site from 2017 to 2019 was calculated to be 76 million tCO 2 eq . This amount is approximately 24 % of the total national GHG emissions in the year 2014 ( latest available report ), as reported in NC3 to the UNFCCC ( Table 4 ), and shows the significant contribution of GHG emissions from the construction sector ( cradle-to-site ).
As shown in Figure 2 , 90 % of the GHG emissions were contributed from embodied carbon in material consumption ( cradle-to-gate ), 7 % from
42 VOL 88 OCTOBER-DECEMBER 2021