A worst-case consideration is to move the pipes to 'warmer' locations, if possible. At least insulate the pipes w/pipe insulation. The Home Centers sell them in long tubes. The wall insulation should be BETWEEN the outside wall and the pipe; not the pipe between the outside wall and the insulation. Do NOT compress the insulation as you pass it BEHIND the piping. Instead, make a 'cut-out' in the insulation. Insulation loses its R-value if it's compressed! Properly installed wall insulation along w/the pipe insulation may work. Once you've made the cut-out in the insulation and installed it (after you've put on the pipe insulation), cover the rest of the cut-out w/the insulation you, well ..., cut out. Again, DON'T go compressing it into place. Go ahead and use some duct tape, or something (if necessary but probably not) if the insulation won't stay in place. It should be able to stay in place on its own.
My best to ya and hope this helps.
Jay J -Moderator
PS: Don't rely on that electrified heating 'strips' that you wrap around pipes. Should the electricity go out, or it fails, you'll have BIGGER problems !!!