How old is your house? Have you made sure that there is no knob and tube wiring?
-renee

It may make it better (if insulation winds up on the cold side). It might make it worse (if any insulation gets blown between the heated room and the pipe.)

To make it more effective, you might want to consider opening the wall(s) and placing the insulation where you want it. This is a bigger project than the blow-in stuff, I realize. But it will also allow you to put in a vapor barrier in the wall.

Another solution, though a royal pain to live with for more than a day or so, is to have a plumber install shut-offs and drain cocks on these pipes in the basement so you can drain the pipes out during a cold snap. You could still use your plumbing during the day if you opened the shut-off and blew out the line at the highest point. Repeat the drain process every night.

Unless you live in a really cold place, you might only have to do this a few times per winter (or if you go away for a few days when it might get cold, or you lost power....)

This is hard one, and why I try to always keep my pipes inside the house, not the walls. But you know, I also always intall the shut-off/drain thing on every line as you never know when it will come in handy and it's arelatively cheap thing to do.

If energy costs drive you to keep the heating even a few degrees lower this winter, it may be more of a problem than in previous years.

ALways thaw frozen pipes with a hair dryer, never a torch, assuming you can get at them!

Molly

Mush,
I did think of another thing that might help a tad - install pipe insulation on any portion of the pipes you can reach in the basement. Even this small addition may help enough to save you, as the water will be "warmer" when it reaches the cold area of the wall, if it hasn't cooled off in the basement.
Molly~

If you decide to blow in insulation, use an expanding product like icynene, I would not blow in fill product like cellulose for this purpose. Expanding foam will fill the cavity pretty good, and you would avoid opening the wall like Molly suggested.

I assume this is a cold water pipe?

This is a project my dad I did the latter part of last winter. I had already gutted the kichen, it wasn't salvagable, and discovered pipes not really in the wall, but between the old plaster and drywall that a PO did (plumber said definately a diy project and done incorrectly). Before any plumbing was rerouted to not be in the wall, is when my dad and I blew in insulation. You could tell the 1 corner in the kitchen had insulation, but that was it. We were fairly confident there was no other insulation except some in the attic. We blew in cellulose. We did it from the inside by measuring over from a corner about 8". He then used a 1" hole bit. This is where my dad got creative :) He had me find an old wire hanger and he first straightened it out and then made a bend in it. He put it in the hole he had drilled out and went over to where he found the stud. Then he measured how far over to get more accurate for the next hole, measuring to try to be 16" apart. He made holes all around in each room on the outside walls and below windows. At Menard's, when you buy cellulose, you're given a days free rent of the blower. We spent one day drilling holes and the next day filling them. We started on the first floor...only to discover that we have a balloon structure and some of the cellulose came out underneath the baseboards upstairs (the quarter round had been removed long before us). We could have just made the holes upstairs, but live and learn. We did the upstairs the next week, using a blower the carpenter I'd hired had. The kitchen and 1/2 bath were different since I'd gutted them. In those 2 rooms, I used the roll insulation. Both were sooo easy to do and who knows how much it saved us by not hiring the job done. I can also say that the heating bill was virtually cut in half after blowing in the insulation. The holes were easy to fill with plaster when we were done, either the carpenter or myself did those. Tony's way was easier than mine. He already had plaster made up for another room he was working on and took a bag, filled it, cut a small hole in the bottom and squeezed out the plaster into the hole. Then it was up to me to sand them down (they tended to expand out). I was just using a putty knife and trying to get it in the hole. If you're not sure where the water pipe is, (is it between the interior and exterior towards the back, or more towards the inside) I'm not sure this would work for your pipe because of the reasons stated above. But it sure would work for the rest of the house!

If you have pipes freezing in the walls, watch out for wind infiltration from outside, and stop this if possible. We have 6 inches if fibreglass insulation outside the pipes in one washroom. The pipes still occasionally freeze because we can't seal off the wind from outside.

We blew in insulation 10 years ago. And going to pull off caps to check to see how much it has dropped. But last week dug trench around foundation. Added 2x4 foam boards-has stucco look on outside 2 inch thick. And found blocks that some mortar had come loose. Filled that in also.

We had a pipe above the foundation wall by the slop sink freeze up. DH cut a small round 3" hole in the paneling to allow room air to circulate. Our neighbor just lifts the shelf top above his pipe. These work here because we don't usually have extremely long, extremely cold spells.