The problem of stress-wave generation in a linear thermoelastic solid by internal heat addition is investigated on the basis of a one-dimensional model of material response. A method of integration of the governing equations is given for the case of power deposition with arbitrary time and space variation. Closed-form results are presented for the half-space and the finite slab for power deposition which is a step function in time and exponential with distance from one surface, assuming negligible heat conduction. The influence of thermal diffusion on the stress field is estimated in terms of a dimensionless parameter representing the ratio of characteristic times of stress-wave propagation and thermal diffusion.