I have to run 4" drain pipe for the washer that is on the second floor, but, the building being old and all, I wouldn't want to rip the floors, instead, I was thinking of running the drain on the outside of the house and then go back in at the basement level. It would be preferable as the pipe would be hidden with other exterior pipes and would not look ugly or out of place. This is for state of CT, so to prevent winter freezing, I was told to go with 4" PVC instead of the 3" recommended by washer manual. Any suggestions? Drilling through the floor to run the pipe on the inside is not possible, so, what options do I have?
Thanks.
Best Answer
I would strongly suggest a "Pipe chase" (box, preferably well insulated) around the pipe on the outside of the house in a freezing climate.
That same box will also help to "improve the appearance" (if the pipe will be "grouped with other outside pipes" as you say they can all be in the box, though I'm frankly puzzled as to what such a group of pipes on the exterior would be in a freezing climate...) and protects the PVC pipe from sunlight.
Whether any single measure (such as oversizing the pipe) or combination of measures will actually "protect from freezing" where you expose a pipe to freezing temperatures is highly dependent on the weather for the day or week, the particular details of the water flow in the pipe, and how they interact. If it freezes more than it thaws, it will eventually build up a plug of ice and be a problem - which is why most folks in cold climates try to avoid having plumbing in the outside walls, much less all the way outside the house.