小型輕鋼構建築屋頂外殼隔熱效能與室內熱環境之研究

A Study on the Outer Roof Heat Insulation Efficiency and Indoor Thermal Environment of Small Light Gauge Steel Buildings.

吳亦騏(Yi-Chi Wu)

指導教授 ： 郭柏巖

朝陽科技大學/設計學院/建築系建築及都市設計碩博士班/碩士(2014年)

摘要

台灣有許多不同使用需求的輕鋼構建築，有屬於工廠與廠房的大型輕鋼構建築；也有屬於臨時性組合屋與貨櫃屋的小型輕鋼構建築，透過反射、阻隔以及散熱等原理進行隔熱，但經過長時間使用造成隔熱層年久失修喪失其原始隔熱效能，簡陋的屋頂外殼隔熱造成內部空間過於炎熱。本研究目的，找出輕鋼構建築外殼隔熱效能較佳辦法，達到舒適的室內熱環境。研究利用小型輕鋼構建築進行室內溫熱環境試驗，實驗方式分別從屋頂外側與內側進行隔熱改善比較，屋頂外側隔熱材為黑色遮陽網與白色隔熱漆；屋頂內側隔熱材為小氣泡隔熱毯與大氣泡隔熱毯共四種材料。
根據實驗分析得知，各隔熱方式半戶外平均溫度相當。屋頂外側進行隔熱較能減少熱直接進入室內，白色隔熱漆熱流量較少時滯效果達2小時最顯著。各隔熱材白天實測平均輻射溫度差僅1.9℃；白天室內屋頂至地板垂直溫度變化趨勢線斜率以小氣泡隔熱毯0.0094斜率較大，但比較各隔熱材170公分處溫度與天花板處的溫差，各隔熱材差距0.4℃，顯示各隔熱材料平均輻射溫度與垂直溫度變化對室內熱環境影響相當。且根據濕空氣曲線圖可知，各隔熱材其室內環境皆不在ASHRAE Standard 55訂定的夏季舒適度範圍。
實驗結果發現，小型輕鋼構建築從屋頂外側進行屋頂外殼隔熱效能較佳且較能降低熱直接進入室內，其中白色隔熱漆熱流進出較少時滯效果最顯著，有效減緩熱進入室內。未來設計輕鋼構建築時需優先考慮室內垂直距離與適當的通風，且於屋頂外殼進行施作與搭建時，最好能先在屋頂外殼塗刷白色隔熱漆或其他從屋頂外側進行隔熱之方法，以達到舒適的室內熱環境。

關鍵字

室內熱環境 ； 隔熱 ； 輕鋼構建築 ； 時滯現象

並列摘要

In Taiwan, light gauge steel buildings are employed for a multitude of purposes; for instance, large light gauge steel buildings are used to house factories and workshops and small light gauge steel buildings are used as pre-fabricated housing units or restructured cargo containers. Thermal insulation is provided through reflection, isolation, and heat dispersion. However, after a long period of use and lack of repair & maintenance, the heat insulation layer gradually loses its initial heat insulation efficiency and the crude roofing insulation of these structures results in overheated interiors. This paper aims to find the best method for ensuring the outer roof heat insulation efficiency for the light gauge steel buildings, thereby maintaining comfortable indoor thermal environment. The paper conducted an indoor thermal environment experiment on a small light gauge steel building. In the experiment, a comparison between outer roof heat insulation and inner roof heat insulation was implemented to see the heat insulation improvement. Four types of materials were used in the procedure. For the outer roof heat insulation, black shade nets and white insulation paint were applied; for the inner roof heat insulation, fine air bubble heat insulation sheets and coarse air bubble heat insulation sheets were used.

An analysis of the experiment revealed that the respective heat insulating methods had similar average semi-outdoor temperatures. The outer roof heat insulation has been more efficient in reducing direct penetration of heat into the interior; furthermore, it’s noted that the white insulation paint had a significant time lag effect of two hours at a smaller level of heat flux. Each heat insulation material had an average radiation temperature difference of merely 1.9℃ during day. As for the slope of the indoor vertical temperature fluctuation trend line from roof to floor in the daytime, the greatest slope, 0.0094, was noted under the fine air bubble heat insulation sheet. A comparison between the temperature at a 170-cm height and the temperature beneath the ceiling showed a temperature difference of 0.4℃ for each material. It is apparent that the average radiation temperatures and vertical temperature fluctuations of the respective insulation materials have similar effect on the indoor thermal environment. Furthermore, according to the psychrometric chart, the indoor environments under the foregoing insulation materials are outside the range of summer season thermal comfort of the ASHRAE Standard 55.

Experiment findings revealed that the efficiency of the outer roof heat insulation applied on the small light gauge steel buildings is better and more capable of reducing direct penetration of heat into the interior. Moreover, the white insulation paint has a significant time lag effect at a smaller level of heat flux, thus effectively reducing penetration of heat into the interior. Thus in the future, it is imperative to make indoor floor-to-ceiling distance and proper ventilation the priority consideration when designing the light gauge steel buildings, and to coat white insulation paint or apply other insulation materials on the exterior roof before constructing and installing the roof in order to make sure a comfort indoor thermal environment.

並列關鍵字

indoor thermal environment ； heat insulation ； light gauge steel building ； time lag effect

參考文獻

15、黃瑞隆、郭乃榕、蔡茹涵、 陳家蓁、林家伃、夏婉珩、朱妤珺，2006，"自然通風教室熱舒適要求調查"，《冷凍與空調》，第42期，pp.47~56。

21、謝恩倉、張源修、侯文祥，2010，"建築屋頂與牆之節能及經濟效益研究"，《農業工程學報》，第56卷，第1期，pp.81~98。

8、許杏瑜、紀杰依、楊明祥、崔祐榮、陳銘雄、林盛隆，2004，"無空調狀態下學校普通教室熱舒適度之探討"，2004台灣環境資源永續發展研討會論文集。

9、許富順，2011，"BIPV建築整合光電模組應用於工作空間之室內光環境探討"，樹德科技大學建築與室內設計研究所碩士論文。

12、傅任淇，2008，"強化建築物外殼隔熱基準與成本效益之研究-以學校類建築為例"，朝陽科技大學建築及都市設計研究所碩士論文。