Journeyman Plumber here, any questions ask away!

[Austin James]

Did plumbing for 7 years before moving to sells, I still own a plumbing company on the side. I can do my best to answer any plumbing questions. Ask away.

[Austin James]

Originally posted by @Eddy Dumire:

@Austin James Thanks for doing this!

I have a 2/1 single story on crawlspace that I'm currently renovating.  There is a single wall that has kitchen and bathroom on opposite sides and I'm doing a complete demo on the bathroom.  Bottom line is I can see almost every inch of plumbing in the house right now.

The house was built in 1962 but it looks like someone has been here before me and has spliced in pieces of PVC into the cast iron drain pipe.  The runs to the fixtures are also a combination of copper and some kind of plastic (not sure about this one).  In total, the entire house is a toilet, bathtub, vanity, and kitchen sink on a single wall that drops down to a crawlspace.  Currently the crawlspace is unconditioned but I'm going to encapsulate it.

I'm thinking I should bite the bullet and just replace almost every bit of plumbing in the house right now rather than close up the wall and wait for something to break, especially since I'm putting nice tile in the bathroom.

So here goes:

1.  Should all plumbing be replaced at this stage or should I just fix it when it goes wrong?

2.  Is it a better idea to just replace what will be sealed up in wall and leave the crawlspace area as it is until something breaks?

3.  I had polybutyl in one house, which of course ruptured.  For that reason I've been a copper loyalist.  Do you promise me that PEX will never ever rupture? jk

4.  Is PEX your #1 choice for a full replacement or do you actually prefer something else like CPVC or copper?

5.  How much time would something like this take a reasonably skilled plumber? 

6.  What would be a spitball guesstimate on costs?  The entire wall is only about 7 feet long.

7.  I have a decent amount of mechanical aptitude.  I've soldered copper and glued pvc drain lines together before.  Is this something I could reasonably do on my own?  I've never used PEX.

Thanks!  Sorry to dump so much on you at once. 

 First off, I would 100% bite the bullet right now. Other than fire water can ruin a house faster that you can stop it. Now to address your concerns

1-fix it at this stage. The wall are open this could be a very easy project 

2-I would replace it all right now. You can just replace every from the drain down. There is no need to replace the vents going through the roof unless you want to. 

3-I have had PEX rupture before, but it was because a framer put a nail almost All the way through it. So when you turned the water into it the pressure finished the job. The PEX pressure threshold far exceeds what you will be putting on it.

4-PEX is my number one choice! For many reasons. Cost is a huge one PEX also doesn't  corrode. Copper 100% will go bad. Another big one for investors is you can reuse fittings, saving cost there as well. 

5-given that everything is opened up. A reasonable plumber would and should finish that project in 1-2 days 

6-most plumbers charge $500-$800 per fixture. So you have 4 fixtures 4 X $800 = $3200. Now that would be on the very very high side. This project without looking at it. Sounds like a project I could finish in a day easy my bid would come in at $2,000-$2500 pending how much demo I would have to do.

7-With very little knowledge and Google you could tackle this no problem. PEX is as easy and it gets, rent a crimper set from lowes or Home Depot. But the piping and fittings and some straps and you will be just fine. As plumbers say the only thing plumber needs to know "Crap runs down hill, and pay days on Friday" 

Hope that helps some!