Environmental assessment tools for buildings are rapidly developing in many countries. All of them claim that they measure “greenness” or “sustainability” of buildings, i.e. if maximum scores are awarded a building is sustainable in some respect. But so far there is no consensus on the interpretation of “green” or “sustainable” in terms of criteria and indicators.

This article explores if different tools point in different directions regarding “green” building design. It also investigates characteristics of assessment tools and consequences of different approaches.

Three distinctly different assessment tools, LEED-NC, Code for Sustainable Homes (CSH) and EcoEffect have been selected. They have three core assessment areas in common, namely Energy, Indoor Environment and Materials & Waste. The content however is different.

The tools have been compared with respect to aim, content and aggregation. They have been tested on a new multi storey residential building. Assessments within the core areas were compared. Measures to improve the overall judgement were explored. The diverging result raises the question how to design environmentally relevant and practically useful assessment tools for buildings.