A quantitative evaluation method for rainwater use guideline

Rainwater use as a supplement to the potable water supply has been demonstrated as a practical and promising alternative solution for water shortage. This paper aims to develop a practical evaluation program for water conservation, in particular, a rainwater use system for architectural planning. The proposed system involves a quantitative methodology to evaluate and improve the decision making for rainwater use systems in building design. Furthermore, a simplified scheme is proposed using daily rainfall probability to provide a new guideline for water conservation evaluation procedures and link to the National Building Code in Taiwan. The practical evaluation method could also be of benefit to the comprehensive applications in other countries. Practical application : This article relates to the practice of professionals in building water supply, sanitation and water conservation areas. The paper introduces a practical evaluation program for rainwater harvesting systems for domestic water-use, which can link to the national building code as a new guideline. The importance of utility performance will be stressed and a method that allows reliable verification for general building categories has been presented. The proposed method has been adopted within the evaluation manual for the Taiwan Green Buildings Level System.