This paper explores the subject of information exchange in order to enhance to the integration of environmental expertise in the product design process. More precisely, the research question addressed is: What is the impact on the resulting product when different sets of information about the design process are given to the environmental expert? To explore this question, a game that simulates a collaborative design process has been adapted (Delta design game), including a role for the environmental expert. Different situations have been created to compare three different sets of information. During the first one, an environmental expert aims at improving a house considering his own point of view, being disconnected from the design team. In the second one, the environmental expert aims at improving this same house considering his own point of view and the main constraints of other experts. Then, in the last one, the environmental expert takes part of the design team, collaborating with other experts. A total of 69 volunteers have participated on the experiments. The results show that: (1) in a disconnected context, an environmental expert is more focused on the environmental issue when he has less information about the design process, and is more concerned about the global feasibility of the product when he has more information;(2) In an integrated context, having more information leads to the best compromise between feasibility and good environmental performance of the house.