Among other things, the disclosure features a thermal blanket including a unitary fabric element having predetermined discrete regions of contrasting insulative capacities arranged based on insulative needs of corresponding regions of a user's body. At least two of the predetermined, discrete regions of contrasting insulative capacities, in one or more first discrete regions of the unitary fabric element, consisting of loop yarn having a first pile height, and in one or more other discrete regions of the unitary fabric element, consist of loop yarn having another pile height different from and relatively greater than the first pile height.