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cp-10/cp-11 mastic really necessary for steam pipe insulation?
Is applying this mastic really necessary for exposed portions of fiberglass insulation placed on steam pipes? There should not be any condensation on the outside of the pipe, correct? So is the benefit just cosmetic? I would like to insulate the straight runs with pre-formed pipe insulation with ASJ and get to elbows and tees later. I'd rather just leave off the mastic if it isn't important.
And if there was a pipe leak, you would probably be better off having a way for water to get out so you notice the leak rather sealing up any exit points and soaking a larger amount of pipe and insulation.