We have a copper cold water pipe running inside an outside wall in a downstairs bathroom that keeps freezing. Finally this winter it burst.
It's a block outside wall with 2x4 studs, very little insulation covered by sheet rock. The pipe is now repaired. The question is how to insulate the pipe to keep it from freezing without ripping out all the sheet rock and starting over.
Should I cover the pipe with the circular foam sleeves used in A/C line sets? I could slide the sleeving along the pipe through the hole I cut in the sheet rock to repair it? Other ideas?