An insulated glass unit is described and includes at least a first glass layer, a second glass layer and a third glass layer disposed therebetween. The third glass layer is separated from the first glass layer and the second glass layer by first and second sealed gap spaces. The third glass layer has a low CTE as compared to the CTE of the first and/or second glass layers. In some instances, the third glass layer has a CTE of less than 70×10−7/° C. over a temperature range of 0-300° C.