This study describes a new method for the measurement of the thermal conductivity of insulating materials in the range from 0.1 to 1.5 W degrees C-1 m(-1) which generally covers polymers, ceramics and glasses. The method is based on modulated DSC and includes no modification or additions to the apparatus itself. One additional calibration step is required to compensate for heat loss through the inert purge gas surrounding the test specimen. Best case precision is in the order of 2%, with mean values compared to literature values within 1%. While work to date includes only temperatures near ambient, measurements above and below ambient seem possible. Further work is also currently in progress to evaluate the applicability of this method to a broader range of materials.