The utility of a stoneware panel covering radiators to improve their energy performance is analysed. These types of panels are normally used for aesthetic purposes, although manufactures argue that they also have a practical use due to retaining heat which is emitted when the radiator is turned off. A theoretical experimental study was thus conducted to verify this claim. The temperatures of four pairs of water radiators were simulated using CFD analysis, one of each pair being covered with a stoneware panel during heating and cooling. These temperatures were compared with those measured using infrared thermography and thermocouples located on the surface of the radiators and stoneware panels. Both the experimental and theoretical methods confirm that the temperature of the stoneware panel during cooling is slightly higher than the corresponding temperature of the aluminium surface of the radiator. This difference tends to disappear, however, and is of less than 2 degrees C only 50 min after cooling has started. (C) 2014 Elsevier Ltd. All rights reserved.