Design and creation of the indoor environment in accordance with the principles of sustainable development and optimization of already existing environment require an integrated approach and collaboration from the earliest preparatory stages of the project. Evaluation of the parameters of the internal environment is necessary for designing buildings in terms of quality assurance of the indoor environment. Address identification of pollution sources is essential to determine the anticipated loads of buildings and design of optimization measures. Ensuring the necessary acceptable quality of the indoor environment can be achieved by minimizing or completely eliminating sources of pollution in the indoor environment of buildings. Each design of the indoor environment should be based on the knowledge of the microclimate components. It is almost impossible to design methods and optimize individual components of indoor building environments leading to an optimal indoor environment without complex analysis of the occurrence of pollutants.