建築外牆材料生命週期之碳排放分析

Abstract

台灣建築物屋齡超過20年的建築物總樓地板面積，約占了超過全體總數的三成，也意謂著台灣建築物普遍面臨高齡化的威脅，面臨需要更新維護的階段，目前油電雙漲，節能減碳是整個綠建築的主要潮流，近年來為了減緩全球氣候急劇變遷的現象，二氧化碳等溫室氣體的管制，已成為全世界首要環保工作重點，更躍居為世界各高峰會的最重要議題之一，過去相關文獻，雖然有探討到外牆材料碳排放量，但是主要都還是在分析外牆材料新建的碳排放，沒有考慮到材料在建築生命週期內建材更新替換及維護頻率，因此本研究將分析外牆材料生命週期，加入維護管理的概念，考慮更新維護部分，一般建築生命週期為五十年，材料壽命跟維護週期均不相同，其所排放之二氧化碳總量也會有所差異，最後本研究分析結果如下所示:清水混凝土碳排放量2.4 (kg-CO2/m2)，石材碳排放量17.3 (kg-CO2/m2)，油漆碳排放量23.64(kg-CO2/m2)，洗石子碳排放量29.66 (kg-CO2/m2)，二丁掛磁磚碳排放量31.68 (kg-CO2/m2) ，Low-E玻璃帷幕碳排放量31.75 (kg-CO2/m2)，鋁包板碳排放量60.46 (kg-CO2/m2)。以上排序可以發現，加入了生命週期更新維護的概念，由於油漆更新次數較多，油漆的二氧化碳排放會比石材高，而清水混凝土因為無外牆材料，只有清洗部分，所以二氧化碳排放值最低。 過往之研究大多只注重新建之碳排放量，沒有考量到維護管理，乃至於整個生命週期的碳排放，本研究分析整個外牆材料生命週期的碳排放，除了分析建築材料生產、運輸、施工及運棄，外牆材料的二氧化碳排放，並且探討整個生命週期內的更新維護，以期瞭解各種不同建築材料生命週期的碳排放。透過本研究的分析結果，可提供業主於選擇外牆材料時，能將更有效地控制碳排放量，達到節能省碳的目的。

House age over 20 years of building floor area in Taiwan, accounting for more than three percent of all the total number of means of building in Taiwan generally faced with an aging threats facing the need to update the maintenance stage, while the surge of the price of oil and electric power, it is the trend to save energy and reduce carbon emission in green building. In order to alleviate the state of severe global weather changing, control on the emission of carbon-dioxide has recently become the most pivotal career of environmental protection, especially jumped up to the most significant issue in World Summit. According to literature, though there are myriads of discussion on carbon-dioxide emission from outer wall materials, they still pay more attention to analysis on emission from newly-made outer wall than to rate of replacement and maintenance of materials in its life cycle. From this, the thesis will try to analyze the life cycle of outer wall materials, including the notion of maintenance and management. When considering the part of replacement and maintenance, the 50 years life cycle of buildings, and the difference between life of materials and maintenance cycle, there is discrepancy of the consequence of carbon-dioxide emission. Eventually, the following are the consequence of my analysis on carbon-dioxide emission from each materials: exposed concrete is 2.4 (kg-CO2/m2), stone material is 17.3 (kg-CO2/m2), paint is 23.64(kg-CO2/m2), external walls with stucco is 29.66 (kg-CO2/m2), external wall tile is 31.68 (kg-CO2/m2), low-E glass is 31.75 (kg-CO2/m2), aluminum board is 60.46 (kg-CO2/m2). From these data, it is clear that the amount of carbon-dioxide emission from paint is more than that of stone materials, because paint was replaced much more times, which is the notion of life cycle included in this experiment. However, because of partially rinsing, exposed concrete without outer wall materials has lower carbon-dioxide emission. In the past, people put more emphasis on newly-built carbon-dioxide emission than on whole emission and maintenance. In lieu of it, the thesis will try to analyze the emission from whole outer wall materials in life cycle. Besides analysis of emission of outer wall sequence and the sequence of construction materials from production, transportation, construction, to dumping, the thesis discuss with the replacement and maintenance in life cycle in order to find out the emission from different life cycle of construction materials. Through the analysis, the thesis tries to provide employers with some useful data while selecting the outer wall materials to reduce carbon-dioxide emission more efficiently.