To investigate the performance of thin fire blanket materials for house protection from wildland fires, a one-dimensional numerical model, which combines conductive and radiative heat transfer, has been developed, solved and compared with bench-scale experiments. Two types of incident heat sources are studied: convective heating from a burner flame and radiative heating from a cone heater. Radiative heat exchange between the blanket and the environment is critical in the performance of the blankets at high temperatures. The treatment of radiation includes the solution of the radiative transfer equation by the discrete ordinate method since in-depth absorbing, emitting and scattering are believed to be important in these thin blanket materials. A number of material combinations were tested and analyzed, including single and double layers of fiberglass fabric with and without aluminum foil on the front and back surfaces. It is found that high heat-blocking efficiencies can be obtained using thin blankets. Interestingly, it is also found that protecting a house from convective heating is a more difficult challenge than protecting it from radiant heating.