I keep going back and fourth with this one.I’m building a new house and in running the supply lines to the two 2nd floor showers is it better to run 3/4 ” cooper than 1/2″ cooper.I know there’s a pressure vs volume thing going on here but I figure I would ask the guys that install this stuff all the time.The horizontal run about 20′,riser run about 20′ I have well water with an oversized deep well pump,with a 40-60 pressure switch. Thanks Greg
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This is easy. 3/4 to multiple fixtures (shower/sink/toilet) and 1/2 to each fixture. Your other option is 1/2 all the way for each fixture but you'd never do it with copper. A great way to do a PEX installation, though.
1/2" to multiple fixtures makes the wife scream in the shower when you flush. 1" to multiple fixtures gives great pressure, flow, and insensitivity to other users but you wait longer for the hot water to get to you.
The ideal system is a recirculating loop of insulated 3/4" for hot and 1/2" coming off to each fixture. Put a circ pump on a timer for the wake-up and bedtime usage windows. Simple 3/4" for cold with 1/2 branches to each fixture.
The screaming wife syndrome is what I'm trying to avoid.Sometimes we might be taking showers at the same time (not together though ,not for this thread anyway)LOL I read in a tauton book that the plumber ran 3/4" within 10" of the diverter valve and I was wondering if there was any great pressure loss?I home run 3/4" to the whirlpool It seems like it wood fill faster.
You want to use a manifold and run Hypex to each faucet/fixture home run from the manifolds
You wife will not inly not scream, she will stroke your neck and kiss your ears. She will.... Oh Never mind! You get the idea..
Excellence is its own reward!
Hey Piff what's going on.I'm curios to what the advantage is to a manifold system?Also how do you terminate at the fixtures,and what diameter does hypex come in? As far as the wife she's happy as heck,I gave her a whole bathroom for herself.She can powder her nose till the cows come home.
and then she can powder the cows, LOL
1/2" hypex.
There is a connection on the end to tie on a valve. From that it is a normal supply to the faucet.
If the toilet and the shower are on the same 1/2" copper line, and someone flushes while the spouse is in the shower, the flush will steal flow from the shower supply, especially if the flush is first on line.
Flow is a function of diameeeeter, length and pressure, and maybe contained volumn.
Imagine that this toilet and shower are both in the upstairs bath with the manifold in the basement, sixty feet away. The length of line is 120 feet between the two so flow is not reduced as much as in a system where the two units are six feet apart, and even better since they each have their own line instead of sharing.
We are using it more for remodeling because of easier installation and cost savings where snaking it can be done instead of tearing open a wall to solder in copper..
Excellence is its own reward!
That manifold system sounds pretty cool.I looked in one of my plumbing books and they have it set up for slab construction.never gave it a thought with conventional construction.Whould the hpex connection go into a drop eared 90o.How is hypex reliability as far as leaks.And if I did go 3/4" cooper do you think flush syndrome would still happen.
The hypex will never leak. The fittings at ends might. They are a sort of compression ring deal so a quick touch with a wrench takes care of it.
Installation is much faster so savings are in labor cost. Imagine pulling a piece of rope instead of soldering a dozen elbows and joints between hither and yonder. And remember that all those joints are potential leaks.
Another reason I like the hypex is that a lot oif these homes are seasonal here. They can handle feezing better than copper without splitting open.
But - Yes, you can accomplishe the same thing with copper home runs to some degree. My own house has copper home runs and I don't suffer in the shower when anybody else flushes. My home runs are only about 25' from the pressure tank. 1/2" CU lines..
Excellence is its own reward!
Damm Piffin do I wish I ran hpex for the rest of the house!This stuff sounds almost too easy and fast.I was a contortionist for some of the copper lines I ran.I like the freeze advantage to. I also like the idea of throttling down at the manifold everything in one spot.I'm almost done except for the shower lines,the wife will kill me if I start ripping out the copper I just put in and start running something new (LOL) Hummmm -maybe I could send her away for a few days- Hummmmm!
I finished the lines in 3/4' copper what a pain.Piffin,Dave and everyone else who suggested hpex thank you. I had already started with copper. I will never use copper again!And for the other suggestions like the two diverters and shower heads (done deal) Thank you all for your suggestions!!
"I home run 3/4" to the whirlpool It seems like it wood fill faster." Yes, certainly for a whirlpool or maybe for someone who is seriously into baths. Beyond 3/4" and all the pressure loss is in the tub valve anyway, so I wouldn't go to 1".
I do use 1" to a full-bore ball valve for fire-protection water. Hose bibs have so much pressure drop (being globe valves) that they reach their limit watering the lawn. Ask nicely at the fire station and they might give or sell you for cheap a retired 1 to 1-1/2 fire hose.David Thomas Overlooking Cook Inlet in Kenai, Alaska
Dave (Ask nicely at the fire station)( your cracking me up!!!)I can just walk down the stairs from where I'm writing this and grab a length off a pumper or hose rack( LOL) I can grab 1 3/4", 2 1/2", or 4" Or are you psychic and already knew I was a firefighter????
"Or are you psychic and already knew I was a firefighter????"
Nope, I didn't know. Only mildly psychic (knew who was calling sometimes before they invented call ID). But I've never figured out more than 5 out of 6 on the lottery numbers.
The retired fire hose comment applies at least in my small town with a widespread problem with beetle-killed spruce. Maybe not in the big city.
I wish someone would mass-market something meater than 5/8" and 3/4" garden hose. There's plenty of bigger stuff around but per foot, per ID, or per pound, its cost so greatly exceeds what Home Depot sells. Yet if I'm trying to wet down the perimeter of my house, I'd like a lot more than 8-10 gpm.David Thomas Overlooking Cook Inlet in Kenai, Alaska
It was my understanding that pressure-balance valves are intended to prevent big temperature swings even if pressure to the shower drops.
I know this is America, and conservation is no longer fashionable, but have you considered low-flow shower heads? I imagine 1/2" pipe would be fine for those.
Al Mollitor, Sharon MA
Al did you mean temperature swings or pressure swings?I have to admit I don't know much about pressure bal. valves.As far as the low flow shower heads I've tried them but to be honest I work hard and When I take a shower I want to take a shower and enjoy it,also conversation is a good thing!!
As I understand it, pressure-balance valves prevent swings in water temperature so no one gets scalded by hot water if pressure drops in the cold line. So, if someone flushes the toilet, pressure may drop in the shower, but the temperature should stay about the same. These valves are now required by code by many, if not all, places in the US.
Al Mollitor, Sharon MA
Al is this a separate type valve(where on the line would it go)I thought the diverter ,faucet,etc.. have them built in?
A pressure-balance shower and/or tub valve is a very common modern valve. It's the single-handle shower valve you see everywhere these days. A common brand around here (MA) is the Symmons Temptrol, but I'm sure all the major brands have them now. The hot and cold supplies run into a mixing valve and water of the temperature you select comes out for the shower or tub. There is a device in the valve that shuts down the hot as the cold pressure is reduced. This is to prevent scalding, which can be especially dangerous for people who may not be able to jump out of the way quickly, such as babies, the elderly or people with disabilites. They also have a maximum temperature limit setting, and some plumbing inspectors measure the max. temp. to be sure it's not too high. An additonal benefit is that the temperature doesn't change much even if the pressure is momentarily reduced by a flushing toilet, etc. If you buy a new valve today, in all likelyhood it will be a pressure-balance valve.
Maybe a plumber can help us out here.
Al Mollitor, Sharon MA
Pressure balanced tub/shower faucets have the balancing mechanism built into the faucet. Basically, they have a piston-like device that slides back and forth in response to changes in the pressure of the hot and cold water supply, keeping the temperature fairly constant. Symmons calls their models Tempitrol, Moen calls their Posi-temp and Delta uses terms like Scald-guard and Monitor.
What Dave Thomas said. 3/4"to the last Tee in a run. 1/2" to all fixtures.
Make sure there is at least 1/8" per foot slope in all runs with a valve to air at each high spot and a drain at each lo spot. I rip 2x4 into 1/2" increments and place at 4'OC for slope.
Isolate pipes from all structural members, foam pipe insulation works great, cut a piece into 2" pieces and put at each pipe clamp. 1 1/2" conduit clamp works well for 1/2" and ok for 3/4".
figure out how you're gonna' drain that last hot water riser that comes off at a low spot.
MAKE SURE the solder joints are cleaned to raw copper before flux and solder. After each solder joint has cooled below sizzle, wipe with damp rag to remove excess flux.
After water is turned on run each valve full on for 15 mins without aerator screens.
SamT
Sam:the clamps I'm using are the insulater type(Oatey 1 3/8" hole( I probably will use some good pipe insulation maybe the refrigerent type to deaden the sound.Is the pitch for water hammer or to drain? Thanks
figure out how you're gonna' drain that last hot water riser that comes off at a low spot.
Good clamps
For drain, not critical if you don't freeze, but still good for repairs/remodels, and a sign of quality.
SamT
Guess I better stop trying to make everthing so level Damm I'm never gonna finish this house.LOL
Greg
Are these showers going to be just one valve with one shower head or are you going to have any hand showers and or body sprays operated thru a diverter or a second shower valve if so 3/4 would not be a bad idea in either "hepex" or copper
Thanks Kevin
KC I was thinking of doing one of the showers with two heads and two diverters but I'm not sure if that's the way the system should be piped.And I'm not sure that my well would handle it (5 gal per min@ 500' with an over sized well Xtrol tank)Although I was wondering if I matted two well Xtrol tanks together in tandem if that might solve the problem
Has anyone heard about a Thermo Siphon it gives you a hot water circulation without a pump for instant hot water at the shower. An insulated hot water line is started on the top of the water heater run only horizontal and up just upstairs to the last fixture. The line is return to an added "T" on the drain valve of the water heater. This thermal loop has hot water rise to the top of the loop and then return because the lower temperature. Just make sure you remove the short pipe on the top of the water heater, it has a groove on it, it has a check valve inside.
Sounds interesting anybody try it in the real world!
I ran 1/2" WIRSBO pex from my 1" manifolds....homerun to everywhere. They use expansion of the tubing, no crimp. I love it. I've never seen a failure, but I'm only 1 year or so in water now. Billions of feet in Europe...
I put two independent shower heads/faucets in my shower downstairs. I thought it was romantic...maybe my next wife will agree! LOL When I turn one on with the other going, NO CHNAGE in temp or pressure. Flushing a toilet...no change. It's a wonderful thing...two separate heads, two separate temperatures.
To be honest, when I am sore, it is wonderful to stand in the shower, one on my back, one on my chest, different temperatures...LOL. It's pretty damned theraputic!
You guys are gonna get me in trouble with this one,if I start changin things again.LOL
I've seen over a dozen jobs 20 -30 years ago by plumbers who no longer plumb. If it dont work, you add a circulating pump.