A new collaborative environment has been constructed recently, in which a human-shaped virtual agent can communicate with a real human through both verbal and nonverbal ways. The collaborative environment is very promising as the next generation communication environment, but there exists a problem the workload for the construction is too large for the practical use. In this study, the system for simulating the collaborative environment is divided into several subsystems according to its function, and for each subsystem a new construction method to reduce the construction workload has been developed individually. In this paper, newly developed construction methods are described such as an object-oriented method for constructing virtual spaces, an affordance-based body motion synthesizing method and a modeling method of the virtual agent¡Çs behavior using Petri-net.