Just like a Ronco product, "but wait, there's more!"

FYI: I don't think it's probably that relevant to my questions, but we do have a 1925 cast iron hot water boiler for heat, and hope to replace it (before it dies a violent death) with a higher efficiency boiler as soon as we can afford it, and would switch the domestic hot water to an indirect tank if we did. We'd also like to switch from the old cast iron radiators to under the floor PEX radiant if we can do it without destroying the 125yr old main floor oak floors (by installing from basement). Like I said, probably non sequitur, but figured I'd toss it in.

Also we aren't married to the idea of PEX, in fact I have a bunch of copper pipe and pieces in my basement ready to go, it's just that it LOOKS so much simpler, especially to DIYers who have run a lot of wiring. Am I crazy?

TIA!
Hunzi
chief procurement and planning officer for this house

1. Are we a good candidates for Pex?
2. Branch or Home run?
3. If you do Pex as Home Run/Manifold do you run one line to each location (as in 2nd floor bathroom then branch to each fixture) or to each fixture (2nd floor sink, 2nd floor toilet, etc)?
4. If we do manifold with one line to each location, should we run another manifold under the sink to break it up?
5. Is it better and/or cheaper to use a manifold without valves and put valves at each fixture location.
6. What about tubing/pipe size? Same weird mix? 1/2" from a manifold?
7. Should we worry about the 3/4" to 1/2" to 3/4" thing at the meter?
8. Any opinions on the plastic type connectors vs the copper/brass ones?
9. See any other blinding errors we've missed?
10. Anyone want to come help for a pretty good steak and a bottle of their favorite beer? ;-)

1+2. I like to install pex but i love the look of copper. It's great your water main to street has been upgraded to copper. I don't think it matters if you run pex or copper. I have been running pex for eight years and have never had a problem. I would base a home run system off of were my mechanical room is situated. If it is in the middle of everything, then it might be a good idea. If your on one end of the house and have long runs and you might want to recirc your hot line, than it might be a bad idea. If you want to do shut-offs and have all your fixtures labeled with a key code on your home run manifold, than it might be a good idea. On most custom homes (10-20,000 sqft) I will usally run one-inch copper trunk lines and branch off of it with 1/2" pex through the entire structure, then I can run a recirc back to my mechanical room. This works great with biolers, and indirect tanks. The indirect tanks we use have a recirc port and the biolers have a recirc pump control (on 3 minutes off 7). And the copper trunks look great.

3. If I am running a home-run system with shut-offs and labels then yes I will one h/c to each fixture. But if the client does not request us to go into that great of detail, I always make sure that the tubs, showers, kitchen sink, and hose bibs have there own 1/2" h/c. I will put tiolets, ice box, and lavs together.
   
   4--?

4. I do both. I buy manifolds with shut-offs or with-out, the manifolds with out shut-offs are cheaper, but i always put shut-offs at fixture, Neither of witch are required by my code.

5. I use the same rule as with copper 3 colds, 2 hots for 1/2". The Vangaurd pex system comes with 3/8 pex for lavs and tiolets. I have never installed it though. I am often running one hot and one cold 3/4 inch to a tub or shower and reuqires 9gpm or greater.

6. Get the 1/2inch out of the equation.

7. Connections for what?

Rick,

Thanks for your reply, and please forgive my VERY tardy response.

I've been pondering what you've said, and reading here at the Plumbing forum, and to be honest, I'm feeling overwhelmed.

Here's where the overwhelmed part kicks in. We've done small, homeowner-type DIY plumbing jobs before: stuff like moving the kitchen drain line, adding a dishwasher and disposer, adding an ice maker, and changing out faucets; we're pretty skilled with PVC (built and designed a pond, with pump and drains); we've added, moved, and removed vent pipes, but I think I've hit the point in my research where I know enough to be dangerous, and I know enough to know how much I DON'T know. Hence the feeling of rising panic.

Our fair city isn't DIY friendly but we could never afford to do any renovations if we had to bring in trades to do it all, so we've always worked without permit but been hyperviligent about over-engineering things and never violating code, in fact, we always shoot for our work to be as good or better than the best trade work available. We've cleaned up a lot of very scary previous home owner DIY messes.

It looks like no pex is yet allowed here (too DIY friendly?), so we're back the copper. Pex home run systems seemed easy to understand and build so they were properly balanced, but I'm having a hard time wrapping my head around the proper sizing and placement of a copper trunk and branch system for the same fixtures.

Right now, the system we inherited has mix of iron and copper supply that feeds:

the boiler supply, laundry hook ups, and 2 hose bibs on the basement level

1 full bath (toilet, sink, and tub), plus 1 kitchen sink (plus DW and icemaker) on the 1st floor

1 full bath (toilet, sink, and tub) on the 2nd floor.

What we want is this:

boiler supply plus 2 hose bibs plus 1 full bath (toilet, sink, tub/shower combo) plus laundry hook ups and laundry sink, plus wet bar in the basement

1 half bath (toilet, sink) plus 2 kitchen sinks (1 now, adding 2nd sink later) on 1st floor

1 full bath (toilet, sink, tub, separate shower) plus laundry hookups on the 2nd floor.

Can I feed all that with my 3/4" main supply? In truth, the only really demanding fixtures are the 2 tubs (one standard tub/shower combo, one clawfoot) and the new 2nd floor shower (which I'd like to plumb with a shower panel or at least a shower head, handspray, plus a few body sprays and a steam generator, but I'll downgrade that to a normal showehead if I can't run that much water). My washer is an Asko, and while we plan to plumb both H & C to both laundry locations, the washer only needs a cold supply, and only uses about 8-9 gallons at a time. It's not impossible we'd want to use both showers at once, but we've never had that capability before. The rest is all toilets and sinks. We can live with no showers while running a hose bib, heck we can't use anything while there's a hose bib open now and the hose just trickles!)

One of the things we realized was going to hang us up with a true home run system using Pex (before we found out it's not code here yet) was that we simply didn't have anyplace we could run that many pipes across the finished basement (the joists run the wrong way and there's only 1 small chase we can use). The main supply line runs in the front of the house, and all the bathrooms and kitchen are in the back half, but the chimney is in the front, so that's where we need to locate the new gas water heater we'd like to add. We need to move the existing electric water heater, which sits two thirds of the way back in the house under the wet wall for the 2 current bathrooms, because that's where we need to put the tub for the basement level bath, and we want to upgrade to gas before that 30+ yr old water heater gives up. Don't worry, we aren't doing the gas/vent for the water heater ourselves, we have a friend who is a contractor who will help us out with that part.

If I have a 3/4" main, that means I need to feed the water heater with 3/4" in, and reduce to 1/2" coming out, right? Also, I need to reduce the cold side of the T before the water heater to 1/2" for the cold supply?

My DH wants to run 1 set of 3/4" trunks for both H & C all the way to the back of the house and then reduce to 1/2" branches. I think he's wrong and that will lead to a lot of balance problems with the hot and cold. I'm also not sure that's enough water to supply all the fixtures. If necessary, I guess we could upgrade the main supply, but it would have to be after we finished and cleaned up any current construction so we didn't get dinged for being handy around the house.

I'm sure I'll have a couple of questions about the DWV side of the equation too, but at the moment, I'm pretty sure we can solve any issues there with little worry. It's the supply side that is keeping me up at night.

I feel bad even asking these questions, because I feel like y'all will tell me to just hire a plumber, and it's not that I don't respect all the training and knowledge that a real plumber has, I simply can't afford to bring in a pro to do this large a job. I also don't want to screw this up!

Thanks for any replies and please be gentle!
Always ;-)
Hunzi

Are you against running the new lines in CPVC plastic? It's acceptable to (national) codes, very DIY-friendly, and a lot easier than copper to install.

Another suggestion: get a copy of 'Codecheck Plumbing' by Taunton Press (from Amazon, or some of the box stores carry it). Besides covering all sorts of plumbing issues, it does go over sizing lines properly.

Thanks! We do own a copy of the codecheck book. CPVC and Pex are both not legal according to the local code. It's a huge pain in the buns! The city is looking at adding the langauage to make "plastic pipes" legal here, but it isn't just yet. Yeah, I live in the middle of nowhere....they don't cotton to these newfangled ideas!

Always ;-)
Hunzi

I vote with DH. Run 3/4" mains and 1/2" tees. At the moment we have 3/4" main to meter then 3/4" copper "7'> to 1/2" galvanized "3'> to 1/2" cpvc to 1/2" galvanized to 3/4" copper. That whole last sentence is coming out and replaced wirh 3/4" copper and 4 1/2" tees to hose bib, toilet, tub/shower and bathroom sink.

Thanks everyone!

We calculated our fixture units, and it looks like our current mishmash of pipe sizes is a little undersized for the number of fixtures we'll have, so we've decided to run 3/4" copper trunks from the meter, for both cold and hot (in and out of the WH), use 1/2" branches, then once we finish plumbing the DIY part of the project, we'll upgrade our service line & meter to 1" if we don't have enough flow. Right now, most of the iron pipe we have is 3/4" anyway.

Always ;-)
Hunzi