Many are the efforts that have been made during a period of time with the hope of somehow enhancing the possibilities of fulfilling the requirements of the client. Still, the building industry continues to show examples with the opposite result. One of them is a construction company, promoting a project as an environmental effort in Stockholm. Despite the good intention they failed and now has to deal with a major fungus problem to an estimated cost of 35 million SEK (Lander & Jensfelt, 2001). The origin of these failures is the design stage and the constructio n phase.

This research project is focused on the early stages of design. Many of the first decisions made during design are of great importance, as they at the end will influence the final result as for example the durability and energy efficiency. The building industry is having difficulties providing knowledge during the design process in order to evaluate different technical solutions. Wrong decisions might therefore result in costly measures to rectify the mistakes. In many cases it has been stated that rather simple mistakes are due to lack of knowledge. Even if the designers are experienced and well equipped with knowledge another challenge for the designers arises which is to make the client understand the consequences of a decision. It is the responsibility of the designer to code and present all essential facts as it is the client who is responsible for the fina l decision.

To overcome the lack of available knowledge and poor communication of information during the design phase the performance indicators are introduced. By using this tool the issues of building physics could be raised, at present unfortunately a knowledge domain with little or no attention in the building process. However, the question is if it is possible to use performance indicators when assessing different solutions of the building, as the tool that provides the first best rough estimate. Will it give sufficient information in order to make reasonable decisions in the early stages of design?

• design
• envelope design
• performance-based building codes and standards