Someone suggested I post here, so moving my original post.

Not sure if this is the right place for it, if it is, let me know where to move... but, recently discovered that my pipes in the exterior wall of my bathroom have the insulation batt on top instead of behind them. (we had to open the ceiling in the floor underneath the pipes for something else). The pipes also have the foam tube insulation wrapped around them, and behind them between the stud cavities looks to be filled with a sheet of drywall (i guess as a air barrier to block any intrusion of air from the outside from the original construction - Exterior of the house is cedar interlocking planks w cedar shakes - original to the house, so prob no vapor barrier although we are thinking of putting in vinyl siding in a few years.

We just moved in, but the bathroom was redone recently, so ripping out the bathroom is not an option.

Was thinking of blowing in cellulose insulation behind the pipes to give them some additional protection from freezing. Is this a good idea? Are there other options?

We had a blown in contractor come in and look, and he said he would pull out the existing batt insulation (again, its in front of the pipes behind the drywall instead of behind the pipes) and fill the cavities with blown, however, I didn't want to remove the batt, as it would also take the vapor barrier with it. But everything i've been reading says the insulation over the pipes is just the WORST, considering it is isolating the pipes from the interior of the house and exposing the back to the exterior. Doesn't look like there is an additional vapor barrier between bath wall and cavity, supposing thats what the kraft paper facing was supposed to do.

Just need to know what my options are, best course of action so i prevent freezing pipes. Is the best way really to remove the batt on top of the pipes and just fill the whole cavity to prevent any airflow? I realize ideally the insulation should all be behind, but now we're remediating a problem inherited to us.

I should add the pipes are over a first floor hallway, where a laundry and bath both have vents to heat the space, it is also in front of a door to an enclosed sunroom (mostly windows), and the roofline of that sunroom also protects the pipes about halfway up since they wouldn't be getting any "wind" exposure due to the added structure in front, but not necessarily eliminate drafts.

Thanks in Advance!