I have to install a utility sink in my unheated garage (I don't think I
have ever seen it below freezing) for my wife's new business... the
floor of the garage is a foot lower than the first floor of the house
(built on slab).
My unfinished utility room is on the opposite side of the wall. The
utility room has the stack on the far side, and incoming cold water and
hot water tank.
I plan on running PEX from the hot and cold lines (copper) to two frost
free taps over the tub (probably not necessary but may as well so they
can be weatherized if needed).
For the drain i believe my best option is to use a under sink sump pump
with a 8 foot header then less than a two foot run to an existing 2"
drain pipe with a vent behind it that runs right into the stack a few
The pump I bought also needs venting and that is right there as well (or
I can use a cheater?).
I am leaning towards taking the drain and vent into the wall to the warm
side right after the check valve so that any leaks at the check valve
would be into the garage. With the water that will always be in the pipe
there should not be any chance of freezing in the check valve.
The only place it might freeze would be in the pump tank, but I could
always wrap it with heat tape if needed?
Your thoughts would be appreciated.