Replacing whole house PVC/CPVC with PEX- need help w/ layout

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Zanne

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My hot waterlines for the entire house ruptured in the recent winter storms. The CPVC entire run is destroyed. We've decided to replace it all (and do cold water at the same time) with PEX.

I'm trying to figure out the most efficient way to run the lines and where to add shutoffs, etc. I want to have a shut-off on every line that comes up through the floor but I'm wondering if it is worth it to have shut-offs under the house as well.

I plan to make some changes to the layout eventually & I want to have the pipes run in such a way that it could easily be altered for it. I'm also considering a PEX manifold of some sort in the south wall of what will be the new laundry room. I actually would have two separate manifolds for hot and cold. Cold one would be in the wall for the laundry room. Hot would be near the water heater. I figure I will need 3 (lav, shower, toilet) and 2 hot (lav, shower) for each bathroom; 1 hot & 1 cold for kitchen (I don't use the water hookup for the fridge); 1 hot & 1 cold for the laundry room; and 1 cold for outdoor faucet at back door.

This is my current layout with notations on changes.
housefloorplancurrrough1notes.png

This is the planned changes- B1 will swap w/ laundry
housefloorplancurrroughmod2.png

I do not have the Pex manifold parts yet and am not quite ready to install them, but I would like to run my waterlines in such a way that it wouldn't be too difficult to add them later. Cold water line for the manifold would come up around where the cold water for the washing machine currently comes up.

Any suggestions on the layout?

Friend is coming out tomorrow to install the pex and we are trying to come up with a plan. Also need to figure out just how much we need but I will need to find measurements of the house again. I think there is a faded drawing my father made that I can transcribe to computer.

Additional info: I'm in the south where it rarely gets below freezing. We've had a few colder winters the last few years and this year was the worst in over 100 years. I have small styrofoam boxes that I can use for some of the pipes that might be closer to the outside of the house-- the space under the house is not closed in-- it doesn't have skirting all the way around so it is exposed to cold air a bit. It's dirt under the house-- it's up on short pillars.

B1 is currently not in use so getting it hooked up is not the priority just yet. Main priority is Kitchen and B2. I hope to get B3 set up soon but none of the water supply lines for it are being moved.

Pex barb fittings will be used for each joint-- although I'd like to limit the number of joints if possible.

Any suggestions?
 
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I use crimp fittings and copper crimp rings.

I run 1” main cold line and branch off with 3/4” to each bathroom and the water heater. 1/2” to each fixture. No more than 2 fixtures on a 1/2” line.

Hot water I run a 3/4 trunk line and no more than 2 fixtures on 1/2” pipe.,

Our water pressure runs around 70psi and I have no complaints.

Install stop valves for each fixture or appliance. Install a stop valve at the well pump, install another before the pipe enters the foundation or before the first outlet in the basement or a closet.
 
Don’t oversize your hot water lines or you’ll be waiting for hot water a lot longer.

Or if you circulate you’ll be wasting energy.
 
Thanks, twowaxhack. I will have to measure, but I suspect the water supply going into my house is only 3/4" (if I can even find where it comes in). I have a shut-off for the main line as well as to the house, outside, and barn inside the well shed. The pipes go underground after that. Once we figure out where under the house it comes up, we then can try to run from that point. I think it is near the back door somewhere, but it might come up near the water heater. It's under the house which is wood on top of little concrete pillars. All points of entry will be through the floor.

If the main source is only 3/4" can I use an 3/4" to 1" adapter to make the pipe thicker to run out and then use reducers to 3/4?

Or should I stick with 3/4" and branch off to 1/2" for each fixture that is 1/2"?

Does this look ok? (if it makes any sense)
waterlinesinhouse.png

I wanted the water line to the water heater run separate from the other lines in case I need to shut off water just to the water heater from below. Now I need to figure out how many tees and fittings I will need. I know this looks messy. LOL. I have to keep in mind that PEX can bend somewhat.
 
3/4 will work but 1” would be better.

3/4 male threads x 1” pex is a common transition fitting.

Water heater shut off goes at the top of the water heater piping on the cold water side only.

Don’t put extra things that can fail into your system that’s not needed. There’s a point to where you’re backing up.....

The idea is to never need to turn a valve off because of a problem.......because you’ve done everything right.

Plus you have the main valve outside plus one at the pump.....plus the pumps breaker......

The hot water can be turned off to the whole house at the water heater.
 
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I have a main valve at the pump but not just outside-- not anymore. The cover for it was destroyed and it got buried-- which leads me to one of the problems we encountered.
Problem 1: None of the local stores had any of the 1" fittings in stock at all.
Problem 2: The bins were all disorganized, people put the wrong things in the wrong place, some of the items listed as in stock online were nowhere to be found, & some of the packs of multiple parts had been torn open and fittings stolen. It took over 2 hours to find what we needed (some of that was spent waiting for an employee to get something down off a very high shelf for us).
Problem 3: No 1" pipe coming up from the ground to the house so we had to go with 3/4".
Problem 4: I think there are two main supply lines branched somewhere underground to supply water to the house. I know my father made it so the hot water was separate from the cold water so the hot water could be turned off while cold remained on. I crawled under there and traced the cold supply to the water heater as far back as I could. When I got to a spot I couldn't fit past, I grabbed the pipe and jiggled it so my friend could find it. He connected to it w/ PEX, feed me the PEX line (which took awhile bc it kept curling up) and I dragged it as close to water heater as I could (couldn't fit close enough). I then worked my way back out--after fighting with some defunct metal pipes that kept catching me and I was getting stuck. Finally got out and friend went under. He connected the main line to the water heater and then ran a line from water heater's hot side to the kitchen sink's hot inlet. Turned it on- no water still, but friend said another pipe that wasn't hooked up was leaking. So we shut the water off & I remembered the separate runs. Lost daylight so we will try again tomorrow. I think there is a separate line for the cold. Didn't get nearly as much done as we wanted bc it took so long to crawl. Friend was dreading it but it wasn't as bad as he thought-- except for him getting slightly zapped by an exposed 220v line that's just under the house w/ no conduit. Gonna have to turn power off and wrap it. I'd do it myself but I can't fit. I had to roll on my back and scoot for most of the way. Cat climbed on me while I was lying down waiting for friend to feed pex under.

While down there I noticed a very odd setup with my drainage pipes. Looks like it was for the washing machine. There was a part that raised up and then had something that looked like it had bolts or something on it attached to the end and it connected to a saddle tee on my main waste pipe. I would have gotten pictures but I didn't bring my phone under.
 
I had a plumber friend get killed by a naked wire under a house. Be careful.

I usually turn all the power offf to a home when I go into the crawlspace.
 
Until I was under there recently, I had no idea it was there. My dad had cleared up most of that crap back in the 80s. Unfortunately, the AC guy apparently ran a new line and didn't bother to seal it in conduit. I'm half-tempted to call him up and chew him out. The tenants also didn't help bc they messed with the wiring and I believe they ran some stuff outside of conduit under the house. My father put everything (except telephone line) in conduit/plastic pipe. I saw a jumble of wires under there without covering & it makes me angry.

Friend is still very sore from it today. Not the first time he got zapped though. Years ago he got zapped while trying to work on a light fixture at his grandpa's house. I think his grandpa turned the switch back on, not thinking about things, and it really got him. He lost feeling in his right hand, arm, and his feet. He was unable to drive for years bc he couldn't feel his feet.

I will turn off breaker to the AC next time we crawl under there.

Confirmed there were two lines coming in to the house. I remembered there was a box just out from under the house that had a lid and the lid broke & it got filled in. I told my friend and showed him the general area I remembered it being in. He found it & dug it out. Two lines going in but no shutoffs. One goes to all the cold water outlets, other went to water heater.

The good news is, once I shut off the tub water (my brother accidentally turned it the wrong way) and the outside cow waterer, the water heater started filling, sinks worked, and toilet filled. We now have working water and nothing seems to be leaking. But we don't have hot water (since I kept the water heater off just in case).

We were both too sore to do much so we decided to take a few days to recover.

All lines appeared to be 3/4" rather than 1". Store was out of some of the fittings we need but hopefully they will be back in when we are ready to resume.

My friend wanted to either cap the 2nd line going to the cold and tee from the line heading to the water heater or to merge that line with the line going to the water heater. I would like to keep the lines separate. I suggested finding where 2nd line comes up, cutting it & putting fittings to convert to PEX. Taping the PEX to the cut off end that goes to whatever fixture (likely the tub). Then I can crawl under to find where it terminates, cut it off, and pull it so the PEX can get to where we need it to go. We really need to clear out all the old pipes that are no longer in use so they don't get in the way anymore. There was a galvanized steel one that was really pissing me off. I'm hoping that 2nd line doesn't go under anything because that will mean that pulling trick won't work.

Worst case maybe I can get some sort of grabber arm to extend my reach and see if my friend can tether the PEX to an old straight PVC line and feeding it to me.
 
Turns out the water lines came in at the very southern corner on the east side of the house. They used to have shutoffs inside a box but former tenants apparently removed the shutoffs so it's just pipes in there. Couldn't find any 1" PEX or 1" fittings locally so went from 1" PVC to 3/4" PEX lines with ball valves on each line. The hot line (starting out as light blue) went from 1" to 3/4" and headed straight to the water heater where it tied in to the existing PVC that goes up into a crawlspace/air compartment under the water heater and air conditioner. The PVC line attaches to a metal hose that attaches to the top of the heater (no shutoff there- but need to add one later). Another metal hose comes out and goes to CPVC which goes through the compartment and under the house. We tied in with PEX under there and ran the pipe in sort of a loop under the current laundry room and then to the kitchen sink. For many months the sink was the only thing with hot water. My friend added a 3/4" tee just under the water heater tie-in to head a line over to the bathroom groups. Somewhere below the closet/toilets a closed quadruple poly branch tee with 1/2" outlets was attached. It then branched to the tubs and sinks. A tee was added under the washing machine to run hot water to it.

For the cold line it runs sort of diagonally across the house under the two bathroom groups and around the closet/toilets area it has an open ended triple branch tee (three 1/2" outlets and two 3/4" ends). One end continues on to closed end triple branch tee. Not sure which line goes where, but they feed the sinks, toilets, and tubs. A tee was added in under the washing machine to supply cold water to it.

We lost daylight & our bodies were aching too much to finish the cold line to the kitchen sink & outside hose bibb. Waiting to recover enough that I can annihilate the blackberry bushes in the way of the entry point under the kitchen sink to be able to reach. It's rather shallow over there.

The sinks and toilets all got 1/2" to 3/8" sharkbite push fittings (as they are easy to check on). The tubs got pex crimp ball valves since on set is in a closet and another is in a wall. Had to cut open the wall and there is a large board in the way that will have to be removed (and repurposed-- possibly as a backer for grab bars) to put in the access panel.

My lav didn't get tied in since the supply lines are copper & need to be removed-- I've ordered new braided steel supply lines. The tubs did not get tied in since we need proper adapters to make them fit, but they have shutoffs installed.

We cut about 10' lengths of PEX for each line and ran them under, tethering them to the old PVC pipes so they would go through the holes easily. Only had problems with one line for my sink because the old pipe sat directly on top of a drain pipe so I had to cut it from below the house. Cue hilarity of mucky brown water (from sediment in the well) spewing all over me from the old supply lines. My friend didn't laugh when it hit him, but I laughed when it got me.

At one point my cat Bethesda tried to use my friend's back as a scratching post so I had to bop her on the head with foam pipe insulation. Aminatu (another cat) climbed on me and wanted attention. The dog, Fippy decided to pee on old pipes to mark his territory.

After my friend got under the house and before he came out, I decided to 86 the blackberry bushes next to the house that tore my head sock off and were generally in the way.
This thing came in handy:
1638412306072.png
4" chainsaw. Gloves did not block thorns though. Has it's own little hard plastic case. Came with a charger, two chains, two batteries, tool for tightening chain, one charger, etc. Without pre-charging the battery, I took out a few small pine trees and a bunch of dried pig grass (tall weeds that are like small tree branches/sticks when they dry). You hold the button with your thumb and pull the trigger. So, no more f***ing thorns grabbed my friend on his way out.

We didn't get the pex hangers up, but for now the pipes are hanging over the old pvc pipes. Once I recover more, I'm going to get a small hammer (since my aim with larger ones is terrible) and see if I can tack up some of the lines to make sure they don't sag too much. I also need to add insulation on to the lines closest to the outside of the house to keep them warm. Because it was so cold and the conduit had been outside in the cold, they shrunk and didn't want to go over the pipes easily.

It's set up so that it will be simple to add in lines for the new lav and toilet, move the laundry supply lines over to the tub, and add in lines for the new position of the washing machine. I'm trying to figure out the most efficient way to run the lines for everything. I suppose a single tee on the hot will branch off to the washing machine, but need to map out in my head the branching for the toilet and lav. Too bad the manifolds aren't sold in less than 3 outlets. A double one would be nice.

Nothing has leaked thus far. When we first turned the water on, it had a lot of air that sputtered and water pressure in the bathroom sink was low, but it is now fine.

So, my rough estimate of the current waterline layout is this:
1638414315105.png

Some of the fittings used:
1638414397342.png
(This was the list I made when trying to come up with what we would need so we had everything). I forgot to include the 1" to 3/4" PVC adapter and the 3/4" fnpt to slip PVC (the one in the picture is CPVC). I used the 1/2" ball valve for the hot side as well. I will keep checking to make sure there are no leaks.

Unfortunately, the shutoff for the cold water under the kitchen sink (prior to this change) wasn't turned off tight enough so it leaked a bit and damaged the cabinet somewhat & ruined the parquet floor (which was already messed up-- but now it is completely toast). The floor underneath seems ok though. I'm going to pull it all up and make sure whatever floor I get next is not thicker than it.

It's so nice to finally be able to use the washing machine again! (It pulled that crap printers pull when you're low on cyan-- refusing to print in black and white-- washer wouldn't function bc it sensed no hot water pressure even when I wanted cold only wash).

The water actually got hot fairly quickly in the kitchen sink when I washed some celery a few minutes ago. Hopefully the bathroom sinks will start to heat faster now too. Always took for frickin' ever despite being so close to the water heater.

I need to get some flanges for the 1/2" pex for the toilets and maybe under the sink (since the holes are too large for some and they start to fall through).

Once I know the more exact layout of pipes and manifolds I will draw it up and print it out to go in the folder with the sketches my father did that showed the electrical layout.
 

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