This manuscript presents a numerical study of a passive heating process of a new structure room using porous‐covering heat‐emitting channels as small discrete radiators. The governing equations are discretized using the finite volume method and the SIMPLER algorithm is employed to handle the pressure–velocity coupling. The effect of porous‐cover to air thermal conductivity ratio (Kr), Darcy number (Da), Rayleigh number (Ra), thickness of the porous‐cover (Ep), and Biot number (Bi) on the heating process of the room is examined. The principal results of this investigation indicate that in the case with Kr > 1, numerical simulations have enabled us to find an optimal value of Ep (Epcr = 0.125) for which the average room temperature reaches a maximum value. In addition, an enhancement in the heating process in the room can reach 77.77% by increasing Ep, Ra, Da, and Kr. Also, a maximum increase in the average room temperature up to 97.77% is achieved at better thermal insulation (Bi = 10).