The article contains a brief description of the developed software environment in the Visual C++ language intended for solving non-stationary heat conduction problems. To create geometric models, the cluster consolidation principle was used, which allows the user to create complex two-dimensional figures using intuitive operations. The presented description includes the actual method of clustering and its software implementation. To solve the heat conduction problem, we used an approach based on integral equations describing the heat transfer process. Its use made it possible to control the accuracy of calculations at each grid point. The paper demonstrates the capabilities of the software environment for assigning heterogeneous materials that have both a regular and an irregular structure. The results of the calculations can be represented both as numerical values and in the form of color maps, and also as three-dimensional surfaces, which makes it possible to get a visual representation of the temperature distribution function at each time layer and analyze critical thermal processes.