Various pipe insulations and apparatuses for insulating pipe that employ magnetic closures are disclosed herein. Pipe insulation is configured to fit substantially around a pipe. In one case, the pipe insulation has a lengthwise split. A magnetic closure is attached to a first lengthwise edge of the pipe insulation along a first side of the lengthwise split. The magnetic closure is configured to magnetically mate with another closure attached to a second lengthwise edge along a second side of the lengthwise split to hold the pipe insulation substantially around the pipe.