I am building a bathroom in the basement. I am a little worried about something though the placement of the stub is against an out side wall. Even though it is underground and won’t get that much cold air to it, I can still put my hand against the concrete wall and feel a decent draft and the wall is cold. I live in Iowa so it does get very cold in the winter. I will put insulation up but is there something I can wrap around the PEX pipe to keep it from freezing or will it be OK if I just make sure to keep it as far away from the concrete wall as possible and keep it on the inside of the insulation?
Thanks for this great service you provide
Brian

PEX tubing is billed as a material that will survive freezing temperatures, even expanding up to 8 times it's original diameter and then returning to it's original diameter when thawed out.

The fittings, of course, are a different matter altogether -- Both the brass and EP (Extruded Plastic) fittings are highly susceptible to cracking and breakage in freezing temperatures.

If the piping and fittings are in a very cold area, then I would suggest you insulate them with regular closed cell foam pipe insulation.

5/8" OD for 1/2 inch pex tubing, 7/8" OD for 3/4 inch pex tubing and 1-1/8" OD for 1 inch pex tubing.