insulating supply pipes

soot_seeker_2

Since it doesn't sound like its in a cold place, I'd be more concerned about a bad pitch or sag in the space, but either can be of concern.

Long Beach Ed

Mark_68

insulating supply pipes

I understand from reading the "Steam Problems?" section on this website that uninsulated supply pipes can result in radiators at the end of the main that won't heat well and water hammer when the system first starts. I've been having both of these problems with the radiator in my first floor bathroom. I can easily insulate the pipes that are exposed in my basement. However, there is a three foot section of supply pipe feeding the radiator that is not easy to get to. It is in an unheated crawl space. The pipe itself is sandwiched between 3" of floor insulation above it and 3" of sheet insulation below it. I don't think the pipe itself is encased in fiberglass insulation. My question is: How important is it to encase the pipe itself in insulation? Thanks.