A thermal distribution assembly for an electronic device is disclosed. The electronic device includes an enclosure defined by a metal band and a non-metal bottom wall formed by glass, sapphire, or plastic. In this regard, the enclosure may include a relatively low thermal conductivity. However, the thermal distribution assembly provides heat transfer capabilities that offset thermal conductivity losses by using a non-metal bottom wall, and also provides added structural support. The thermal distribution assembly may include a first layer, a second layer, and a third layer. The first and third layers provide structural support, while the second layer provides a relatively high thermally conductive layer. The thermal distribution assembly includes sidewalls engaging and thermally coupling to the metal band, allowing the thermal distribution assembly to draw heat from a heat-generating component, and pass the heat to the metal band while minimizing or preventing temperature increases along the non-metal bottom wall.