中華民國內政部建築研究所中華民國內政部建築研究所

一、研究緣起
國內自1999年建立「綠建築標章制度」以來，綠建築政策已成為我國永續發展政策中最重要的一環。內政部建築研究所為改善都市化問題及增加都市水循環，於綠建築標章的評估體系中考慮建築基地保水能力，以基地保水指標來定量評估建築基地中雨水涵養的能力，有效改善日漸惡化的都市水循環問題。此外內政部營建署亦於《建築技術規則》訂立《建築基地保水設計技術規範》，以建築基地涵養水分與貯集滲透雨水能力為考量對象，並透過基地保水指標做為評估標準以利評價恢復水文循環之成效，並於規範中提供基地保水設計原則與施工參考標準及注意事項。
然綜觀國內多年來實施綠建築基地保水指標推動之成果，雖在建築基地已完成許多基地保水項目且已被國人所重視；但直至目前為止，各項基地保水工程皆係參考《建築基地保水設計技術規範》或《綠建築評估手冊》中的簡易設計與施工說明，仍缺乏完整的規劃設計流程、現地適用性的遴選建議、以及設施裝設與工法應用上等的細項說明，且尚未有針對基地保水的技術指引或手冊等相關資料作為實務規劃設計、工程與維護之參考，導致許多基地保水設施規畫設計的計算保水量雖滿足基地保水指標之需求，但實際裝設與運作上常造成效益不彰的情況發生，且若缺乏後續維護管理計畫亦會影響基地保水之成效，故針對此內容有其研究與資料彙整之必要性。
本研究案執行期程為十個半月，爰引本所協同研究計畫需求說明，研究計畫之研究旨在研擬基地保水設施系統性規劃設計與維護管理之相關方法與內容，並透過基地保水設施規劃設計指引(草案)的編撰以提供未來規劃設計之參考。本計劃將蒐集彙整並研析比較國內外近年新發展之基地保水相關政策、工法與規劃設計技術，進而研擬評估各項基地保水設施之現地適用性、配置原則與應用工法等相關內容，並針對計畫成果編撰基地保水設施規劃設計指引(草案)，進而研提後續應用推廣之建議，期能有效提高國內基地保水設施之工程效益與品質。
二、研究方法及過程
研究內容初步之3項研究內容，研究案之工作項目如下：
1.蒐集彙整並研析比較國內外近年新發展之基地保水相關政策、工法與規劃設計技術。
2.研擬評估各項基地保水設施之現地適用性、配置原則與維護管理計畫。
3.研擬基地保水設施規劃設計指引(草案)與後續應用推廣之建議。
三、重要發現
本計畫針對國內外基地保水相關設施與發展策略之應用工法蒐集，並依工法設計內容對應國內規範與綠建築評估手冊所分類的基地保水設施項目進行分類，發現有些國內在建築基地常運用的工法並未於規範與綠建築評估手冊中說明，如：雨水花園；且更多工法雖於規範與綠建築評估手冊的設施項目中舉例，但未有相關的設計建議與標準圖，如：草溝、透水性瀝青、屋頂花園…等。另外，研析國外發展策略應用工法之設計內容時，部分工法可同時對應兩項或三項基地保水設施，而造成分類上的困難，如前述提到的雨水花園即具備三項基地保水設施之條件；以整體理念利用自然土壤滲透保水，與Q1的綠地或草溝相似；而因其設施內部低於周邊道路，故亦如同Q4的貯集滲透空地；再者，依雨水花園規劃的複雜性而定，如欲增進土壤的透、保水能力，可透過土壤開挖並埋設礫石與排水管，即如同Q5的地下貯集滲透。
由於國外發展策略之應用工法仍有許多將設施底部土壤進行開挖並埋設礫石與排水管，而造成分類上的困難，如入滲溝（與Q1草溝相似，但底部土壤埋設礫石與排水管）；因此，將考量把土壤開挖並埋設礫石與排水管的方式而增進透、保水能力，當作一個土壤改良的措施，使本計畫各項分類更加合理化。
四、主要建議事項
建議一
綠建築基地保水設施規劃設計指引出版與培訓講習辦理：短期可行建議
主辦機關：內政部建築研究所
協辦機關：財團法人台灣建築中心
建議針對本年度綠建築基地保水設施規劃設計指引(草案)廣納各領域專家意見，持續針對基地保水與通過綠建材標章之相關廠商進行資料蒐集，並進行手冊排版與內容編修，進而完成綠建築基地保水設施規劃設計指引出版之相關工作事宜。並且建議針對本指引開辦綠建築基地保水設施規劃設計指引推廣講習會，以增進建築師及規劃設計者對於綠建築基地保水技術之認知及規劃設計流程，減少未來不當設計與投資浪費、提高基地保水設施之工程效益及具推廣應用的效果。
建議二
基地保水評估指標考慮生命週期之保水量檢討：中長期可行建議
主辦機關：內政部建築研究所
協辦機關：內政部營建署、財團法人台灣建築中心
綠建築評估體系及其中的基地保水指標係以自然生態與環境永續為目的，由於近年受全球氣候變遷影響，世界各國將倡導節能減碳與循環經濟等作為發展目標，考量基地保水設施係以保水量做為評估依據，然其在建置後的保水能力將依不同設施特性而隨使用時程降低，且不同的工法設計具有不同的翻修或更換時間，但指標評估上未對其進行檢討；故建議應針對基地保水設施從設備產品、施工、建置到維護、修繕、汰換等各階段過程，研析各項設施的能源使用、資源的耗用、污染排放等環境影響，將各項基地保水設施的生命週期納入保水量指標的評估要素，更能達到基地保水設施及其應用工法的合理設計，並提高節能減碳、循環經濟及永續環境之目標。

1.Purpose of the research
The Green Building Labeling System has been established by the Ministry of the Interior, ROC (Taiwan) in the year of 1999. The green building policy has become the most important part of sustainable development policy in Taiwan. In order to improve urbanization problems and increase urban water circulation, water retention capacity at the construction site was included in the green building label evaluation system. In addition, the Construction and Planning Agency, Ministry of the Interior, has also drawled up the "Technical Standard for Water Retention Design at Construction Sites” in the "Technical Regulations for Buildings". It uses water retention index as the evaluation standard to evaluate the effectiveness of restoration of water cycle and considers both water storage and infiltration. It also provides the design principles for water retention, construction standards and precautions in the construction sites.
Having implemented water retention index for many years, a lot of building have completed water retention projects. But in designing water retention facilities, both "Technical Standard for Water Retention Design at Construction Sites” and “Green Building Evaluation Manual " will be used. They provide the brief description of design and engineering but lack complete planning and design processes, selection suggestions for site applicability, and detailed descriptions of facility installation and application of design methods. Therefore, the calculated water retention capacity in the planning and design of many projects meets the base value of water retention index. But the actual installation and operation often lead to ineffective effects. Also the lack of follow-up maintenance and management plans will also affect the effectiveness of the water retention facilities. Therefore, this research is required for improving those drawbacks.
This research project period takes ten months. Based on the requirements of the project, it aims to carry on the systematic research on surface runoff harvesting systems at construction sites. Firstly, collecting policies and technologies related to water retention facilities of newly developed in domestic and abroad in recent years. Based on those results, the planning and design guidelines (draft) for water retention facility, which includes design method and suggestions for subsequent application and promotion, will be developed. With this guideline, engineering efficiency and quality of water retention facilities will be improved.
2.Methodology and procedures
Contents of the research methodology and procedures include following three items:
Collect policies and technologies related to water retention facilities of newly developed in both domestic and abroad in recent years..
Develop and evaluate the on-site applicability, configuration principles and maintenance management plans of various water retention facilities..
Develop the planning and design guidelines (draft) for water retention facilities at construction sites and suggestions for subsequent application and promotion..
3.Major findings
This project finds that some design methods for water retention commonly used in construction sites are not described in the specification and green building evaluation manual such as rain gardens. Also some design methods have examples in the technical standard and manual but no relevant design suggestions and standard drawings such as: grass trenches, permeable asphalt, green roof, etc. In addition, some design methods listed in reports from abroad are similar to two or three facilities of water retention methods in domestic technical standard and manual. It causes confused for architects and difficulties in classification for water retention methods. For example, rain garden has the capacity of infiltration to retain water. It is similar to the water retention method of green space or grass ditches in Q1 classification in Green Building Evaluation Manual. Also the elevation of rain garden is lower than the surrounding areas and it is also similar to the storage and infiltration open space in Q4 classification in Green Building Evaluation Manual. In addition, capacity of water infiltration in rain garden can be improved by replacing natural soil and using artificial soil and drainage pipes buried at the bottom of rain garden. This more likes method of underground storage infiltration in Q5 classification in Green Building Evaluation Manual.
4.Major recommendation items
Through this research, following two immediate to short- and middle- to long-term recommendations are listed and explained as followings:
Recommendation 1
Publishing the guidelines for planning and design of water retention facilities at construction sites in green buildings and holding training workshops: immediate to short-term
Organizer:Architecture and Building Research Institute, Ministry of Interior
Co-organizers:Taiwan Architecture & Building Center
It is recommended that experts in various fields are widely consulted for the guidelines in planning and designing of water retention facilities at construction sites in green buildings in this year. Continuing collect existing water retention methods which have obtained the green building materials label. In the same time, guideline typesetting and content editing are conducted for the guideline. It is also recommended to hold workshops based on this guideline to architects and planners for the applications of this guideline in designing process. Through workshops, architects and planners will reduce the improper design and waste investment in the future design and improve capacity of water retention. The effectiveness of water retention will be highly improved.   
Recommendation 2
Incorporating the life cycle concept for water retention in the water retention index at construction sites in Green Building: middle- to long-term
Organizer:Architecture and Building Research Institute, Ministry of Interior
Co-organizers:Construction and Planning Agency, Ministry of the Interior; Taiwan Architecture & Building Center
The water retention evaluation index is aimed to natural ecology and environmental sustainability. Due to the impact of global climate change in recent years, most developed countries have advocated energy conservation, carbon reduction and circular economy as national development goals. The water retention capacity is used as the evaluation basis, but after construction, the capacity of water retention will decrease with the time depending on the characteristics of water retention facilities. Different design methods have different renovation or replacement times but they have not been reviewed in the index evaluation. Therefore, it is suggested to study and analyze the environmental impacts of various facilities such as energy use, resource consumption, pollution discharge and other environmental impacts of various facilities in the process of products, engineering, construction, maintenance, repair and replacement. Incorporating the life cycle concept for water retention facility into the water retention evaluation index can achieve the rational design of the water retention facilities and improve the goals of energy conservation and carbon reduction, circular economy and sustainable environment.