DIY: Whole House Plumbing Pipe Replacement with PEX: Any Experiences?

My house is currently an odd mixture of galvanized pipe (probably 80 years old or so) and a little newer sweated copper. I had to replace one piece of galvanized pipe 15 years ago because it filled up and started leaking. So I wonder about the rest.

Has anyone here done a whole house replacement of their plumbing water supply lines with PEX (do it yourself, not hired a plumber)? What were your experiences? What went wrong? How long did it take? Did you have to get extra stuff that you didn’t realize you needed?..


First, I’d worry about code, inspections, licensing and these issues come resale time if you decide they don’t matter to you.

Second, I don’t know that I trust PEX all that much for anything but local work. Certainly not through-the-structure main lines replacement. But maybe that’s just me.

Bad plumbing is one of the things that can keep an older house from selling for years and years, because of the expense and hassle of replacing it all. But I don’t think there’s any shortcuts, PEX included. I’d consider biting the bullet and having a pro do at least the main stuff, even if it takes a second mortgage (a sensible way to pay for such things.) Money is cheap right now.

I, too, am interested in this question. My house is piped with polybutylene and I’ve been dying to replace everything with PEX, and a manifold setup so each fixture has it’s own line. My house is a two stor so that makes the task even harder.

I know it will involve drywall work, but I might be lucky, my hall closet has a lowered ceiling and I think a lot of the piping somewhat junctions there.

Some year, maybe.

No concerns about code, inspections, licensing as plumbing is not inspected in this small rural town.

PEX has proven itself successfully over many decades by this point. Properly done, it is extremely strong, easy to install, cheap, and the lack of fittings between source and fixture drastically reduces the probability of leaks.

One disadvantage is there are several different competing connection systems for fittings, each one requiring a different special tool. Some use compression fittings with a ferrule, others use a tool to stretch the diameter of the tubing at the end and then shrink it back over a fitting, and yet another one uses heat.

So you’ll want to research what connection method you want to use and invest in the right tool for that. Also remember that you’ll need to get the right fittings to transition from PEX to all your different fixtures.

I’ve done it, and trust it. I’ve used the compression system primarily, with occasional use of Sharkbite fittings for tricky connections. It can save you a LOT of work as you can run a long piece of PEX with not a lot more difficulty than running cable, so you can run it through a raceway or behind a wall and save yourself thousands in wall repair, just cutting access holes in a few places. Get yourself a good crimper - don’t cheap out.

One other thing though - if the supplies are galvanized, the drains are probably cast iron and are equally screwed up. And there is no way to replace that stuff without a LOT of work.

In my jurisdiction, no permit or professional was required. The city did require an inspect at the water meter junction for the house line though. Everything else was left to my whim to create a multi-color tubing artistic expression :slight_smile:

Even at time of sale?

Concede PEX has advantages, especially for old work and non-pro installation. Maybe I’m too old-school to be comfortable with the idea of whole-house use. :slight_smile:

My brother is a Master Plumber, and he’s totally comfortable with PEX. The only real failure point is a poorly crimped ferrule ring, and as long as you invest in a good crimper and use it properly, that’s not an issue. And if you buy a big roll of PEX and avoid having any inaccessible joints, you’ll be able to inspect all the joints with water pressure on.

I moved out of my ancient crapshack with its jumbleymuck of galvanized/copper/PVC plumbing into a new space that came as a built shell and I was in charge of getting it fitted out as a living space. I used PEX for the whole thing and it’s awesome. Cheap, flexible, easy to install (so long as you have what you need for the fittings–I was a mensch and bought my contractor the PEX wrench he didn’t already have) and best of all if it freezes it doesn’t break because it’s flexible and doesn’t split when the ice expands it. PEX, propane and a tankless water heater have rocked my world with a thoroughness.

Posting to subscribe, too. I’ve actually gotten my PEX tools and the small bits and pieces, but am awaiting warmer weather so that a disaster won’t leave me too out of sorts.

I may end up only doing a partial conversion, though, because I have no idea how to remove the existing copper running from the basement to the second floor, nor how to thread in the replacement PEX. I’ve no intention of removing walls, so I may limit myself to the basement, or bite the bullet and hire a plumber to do the hard bits (they tend to be ornery with DIYers, though).

My motivation for the project is that I have some shoddy, pre-existing repairs, as well as many non-functional valves, plus a non-working outside faucet. While I could cut and sweat in new copper and valves, it looks like a wholesale PEX conversion is only about 10% more expensive.

How much plumbing have you done before? ISTM, whole house replacement seems like a pretty big project to cut your teeth on. Think about it this way: would you hire even a very good handyman service to do that job? You’d probably hire real plumbers, right? There’s more to it when you’re not just replacing a sink. You’ve got to worry about everything being level, getting all pipe sizes right and venting. It’s not as dangerous as doing your own wiring but its still skilled work. Then there’s how long it would take to do yourself vs hiring some pros. Even one plumber and an apprentice could probably do it five times as fast.

PEX is the best.
I have used it to re-plumb a significant part of a house (both bathrooms from the water heater on-the feeder in the slab burst). I talked to several plumbers who were doing hundreds of houses after Katrina and they said for speed and reliability PEX wins hands down. One plumber in a supply store told a story of he and his crew had to re-plumb and entire house and used PEX and shark bite connectors. When they turned on the pressure there wasn’t a single leak. He was very proud and the other people in the room were equally impressed. I am not a plumber but I understand that sweating a whole house usually means a couple of leaks before the job can be called finished. Not a problem with PEX.

And I concur that redoing an entire house if you are an amateur is a bad idea. There is more to plumbing than running connecting tubes. Specify a PEX job and get several bids. You are far more likely to be happy with the result.

I’d be gun shy after the polybutylene fiasco. That was the “pipe of the future”, too. Mine lasted 15 years before it blew out. My copper is on 30 years, and probably will outlast the house.

Chances are hiring a plumber to do the ‘tough stuff’ after you did all the ‘easy stuff’ may be actually more expensive than hiring a plumber to do everything. The plumber may come up with easier ways of doing everything and avoid the tough stuff. Actually they may rip out/ abandon your work and run it differently from the start.

When we did a complete bathroom reno a few years ago we had to move the stack. We let the pros do all the in-the-walls work but saved money and time by doing the demo work. We opened up the wall and ceiling they needed access to so they could just do the plumbing.

Yep, I ran into this when we added on to the house. The plumbers did not want to attach their work to the plastic plumbing I had done. They went back to the copper at the other end of the basement. And these are the same idiots that ran the water lines 1/4" below the fluorescent light tubes along the way.

If you’re not comfortable doing the verticals, you would be better off if you replaced the horizontal pipes - where the lime buildup tends to be worst.

But the verticals are not that bad. Most of the time, there are “wet walls” - open passages from behind the sink to the basement. You can cut an access hole under the sink and use a set of fiberglass “fish sticks” from the access point to the basement, tape the PEX to that and pull it up. In smaller homes, the upstairs bath is almost always directly above the kitchen to have only one wet wall.

My water is bad (as in corrosive) and it ate through my copper pipes. I had a plumber replace everything with PEX about 10 years ago. I don’t regret it a bit but I sure as hell wouldn’t attempt to do it myself.

FFS, PEX has been used in hydronic radiant heating systems in North America for FIFTY FUCKING YEARS. It isn’t polybutylene, which demonstrated severe problems almost immediately.

PEX is now code for potable water in (AFAIK) all 50 states. Code authorities and plumbers were right to be skeptical and adopt a wait-and-see attitude. They have sufficiently waited and seen. PEX works and is great.