An original thermal model of a single room structure is developed by using the tensorial network-based Kron’s method. The modelling principle is using the equivalent RC-network of wall, door and air constituting the house. For a better understanding, the temperature propagation was assumed only in a 1-D horizontal direction. The problem geometrization is defined in function of rectangular approximation meshing. After the determination of the equivalent thermal resistor and thermal capacitor, the innovative thermal circuit representing the room is elaborated. The methodology of the Kron’s formalism, implicitly described with the different action steps is introduced. The thermal room Kron’s method is implemented from the branch to mesh spaces before the expression of the problem metric. The thermal transfer functions (TTFs) at three cases of indoor points, situated near, middle and far of the door are established from the Kron’s problem metric. The feasibility of the room thermal Kron’s TTF model is validated with SPICE TTF simulations in both frequency and time domains. The thermal cut-off frequencies are verified with very good correlation between the established TTF model and simulation. An excellent prediction of transient responses with unit-step and arbitrary waveform temperature signals with a minimal and maximal amplitude of about 20◦C and 40◦C is proposed. © 2020 Institute of Electrical and Electronics Engineers Inc.. All rights reserved.