I am remodeling a bathroom and want to move the water supply lines for the pedestal sink. They currently come out through the floor about 2" in from an exterior wall. This makes them somewhat of an eyesore with a pedestal sink. I want to move the supply lines so they continue through the floor to the exterior wall, then run up the exterior wall to come in through the wall instead of the floor (ie. no change in sink location - just move the supply lines).

This bathroom is at one corner of the house (ie. has two exterior walls), and is located over an unheated garage. The wall that I would like to move the supplies to is one of the exterior walls.

My concern is whether the lines were originally not run up through the exterior wall per code to avoid freezing (perhaps because the space under the bathroom is unheated?)

We live on Long Island (Suffolk County), where it does get cold on occasion.

Do I have to be concerned about freezing if I run the supply lines through an exterior wall?

Thanks in advance.
GuyC

Yes you do need to be concerned about freezing, but not code. It seems to me builders go out of their way to run water lines in exterior walls, often resulting in frozen pipes. Since you are remodeling, a little drywall repair shouldn't add too much to the job. I would remove the drywall over the wall cavity you will be running the pipes through. Remove any insulation to above where the pipes will go out to the sink. Fit a stop, wood, drywall, etc. above where the pipes will come through. Caulk the joint between the sheathing and studs. Run the pipes, and cover them with the foam pipe insulation. Caulk between the pipes and the plate where they come up through. Careful replace the insulation in the wall cavity between the pipes and the outside sheathing. This is overkill, but frozen pipes are a headache. Nobody ever regrets doing it right the first time. Replace the drywall, and tape and mud the seams.

Thanks for the quick answer...

Getting access to the bay where the pipes will run is not an issue as I need to re-drywall the entire powderroom (walls are covered floor to ceiling in badly dated tile).

Off to find the wrecking bar...