Some musings about copper pipe

[Ultradog MN]

I replumbed the entire house when I remodeled 12 years ago. Used type M copper pipe throughout.
Some simple arithmetic shows that to get hot water to the kitchen sink - or to a 1/2 bath at that end of the house we are heating 10 lbs of copper pipe each time we wash our hands or rinse a cup.
I am thinking about replacing the copper hot water pipe with Pex. The heat loss would be much less so less energy used, we would get hot water sooner and we'd use less water.
The water lines are exposed and run across the joists in the cool basement so it would be an easy job to run the pex in the same pipe hangers that the copper is in.
I have the skills and the pex tools so it would be afternoon's work and maybe $60 in parts.
I'm thinking it's worth doing but what says the brain trust here?

 

[Dusty MI]

We moved into an old house in the late 60's, that had Galvanized plumbing that I changed & added CPVC, this was before Pex.

 

[johnlobb]

You will probably need more hangers, PEX is pretty limp compared to M copper.

 

[SARG]

I doubt there would be any notable "value added".
Same as when someone changes their oil from 10W-30 to 15W-40 ...... the engine won't demonstrate a difference.

 

[sandcastle1]

I replumbed the entire house when I remodeled 12 years ago. Used type M copper pipe throughout.
Some simple arithmetic shows that to get hot water to the kitchen sink - or to a 1/2 bath at that end of the house we are heating 10 lbs of copper pipe each time we wash our hands or rinse a cup.
I am thinking about replacing the copper hot water pipe with Pex. The heat loss would be much less so less energy used, we would get hot water sooner and we'd use less water.
The water lines are exposed and run across the joists in the cool basement so it would be an easy job to run the pex in the same pipe hangers that the copper is in.
I have the skills and the pex tools so it would be afternoon's work and maybe $60 in parts.
I'm thinking it's worth doing but what says the brain trust here?

you are still heating up the same amount of pipe. insulating the pipe might show you a savings. good luck

 

[chuckthin]

I used 3/8 pex to replace 1/2 and shortest run possible and now get hot water more than twice as fast. May not work on long run because
volume will be less.

 

[Steve A W]

you are still heating up the same amount of pipe. insulating the pipe might show you a savings. good luck

Here's a video of the difference insulation on copper pipe makes.

 

[jimg.allentown]

Here is suggestion that nobody has yet suggested. Since there is a distance issue, and it only supplies the kitchen and a half bath, what about adding an auxilliary water heater somewhere in the half bath or kitchen? Like under the sink in the kitchen or in a closet in the half bath.
No matter the material or insulation, the water in the pipe will not stay hot for any extended length of time thus rendering the insulation or material irrelevant. An auxilliary heater would be more efficient in the long run AND significantly reduce the time waiting for the water to get hot.

 

[Russ from MN]

Here is suggestion that nobody has yet suggested. Since there is a distance issue, and it only supplies the kitchen and a half bath, what about adding an auxilliary water heater somewhere in the half bath or kitchen? Like under the sink in the kitchen or in a closet in the half bath.
No matter the material or insulation, the water in the pipe will not stay hot for any extended length of time thus rendering the insulation or material irrelevant. An auxilliary heater would be more efficient in the long run AND significantly reduce the time waiting for the water to get hot.

That's what we did, and it works great! A 2 1/2 gallon tank type heater under a bathroom that's 50 feet from the main heater. Now we get hot water quickly and it doesn't change temperature during a shower. Plugs into a 120 v receptacle.

 

[1948CaseVAI]

I replumbed the entire house when I remodeled 12 years ago. Used type M copper pipe throughout.
Some simple arithmetic shows that to get hot water to the kitchen sink - or to a 1/2 bath at that end of the house we are heating 10 lbs of copper pipe each time we wash our hands or rinse a cup.
I am thinking about replacing the copper hot water pipe with Pex. The heat loss would be much less so less energy used, we would get hot water sooner and we'd use less water.
The water lines are exposed and run across the joists in the cool basement so it would be an easy job to run the pex in the same pipe hangers that the copper is in.
I have the skills and the pex tools so it would be afternoon's work and maybe $60 in parts.
I'm thinking it's worth doing but what says the brain trust here?

Why do you care? Seriously?

 

[Janicholson]

Here's a video of the difference insulation on copper pipe makes.

The amount of heat it takes to heat copper is 1/2 the amount it takes to heat PVC (and other plastics are worse). so if the plastic weighs less than 1/2 the copper per foot of run. it is a even match either way. The copper will get hotter quicker, but the temp change for plastic will take longer. Insulating the copper is likely easiest and least expensive. Look up specific heat. Jim

 

[wore out]

I replumbed the entire house when I remodeled 12 years ago. Used type M copper pipe throughout.
Some simple arithmetic shows that to get hot water to the kitchen sink - or to a 1/2 bath at that end of the house we are heating 10 lbs of copper pipe each time we wash our hands or rinse a cup.
I am thinking about replacing the copper hot water pipe with Pex. The heat loss would be much less so less energy used, we would get hot water sooner and we'd use less water.
The water lines are exposed and run across the joists in the cool basement so it would be an easy job to run the pex in the same pipe hangers that the copper is in.
I have the skills and the pex tools so it would be afternoon's work and maybe $60 in parts.
I'm thinking it's worth doing but what says the brain trust here?

Insulate the pipe and install a hot water recirculation pump.

 

[DoubleO7]

No matter the material or insulation, the water in the pipe will not stay hot for any extended length of time thus rendering the insulation or material irrelevant.

This
The only benefit of changing to pex or insulating the pex or the copper would be the interval between hot water use.
With copper the heat loss is faster , so your heat is gone sooner.
Insulation would delay heat loss and allow a longer idle time.
Naked pex, I would guess would not give a longer idle time than insulated copper.
Insulated pex I would guess would give a longer idle time.

If it is easy to run new piping maybe look at making the hot line recirculate back to the water heater and insulate the lines.

 

[jimg.allentown]

Why do you care? Seriously?

Why would anybody care? Because this is a community, and we all help each other. One asks for help in an area out of his/her area of expertise, and those with more experience will give him/her helpful information. THAT is why I or anybody else CARES!!!!

 

[DoubleO7]

Why do you care? Seriously?

Probably because he and the Mrs. want hot water now vs standing there waiting and waiting and waiting.

 

[SARG]

Some simple arithmetic shows that to get hot water to the kitchen sink - or to a 1/2 bath at that end of the house we are heating 10 lbs of copper pipe each time we wash our hands or rinse a cup.

That would be a remarkable spreadsheet to understand.

 

[Frank(Mi.)]

I replumbed the entire house when I remodeled 12 years ago. Used type M copper pipe throughout.
Some simple arithmetic shows that to get hot water to the kitchen sink - or to a 1/2 bath at that end of the house we are heating 10 lbs of copper pipe each time we wash our hands or rinse a cup.
I am thinking about replacing the copper hot water pipe with Pex. The heat loss would be much less so less energy used, we would get hot water sooner and we'd use less water.
The water lines are exposed and run across the joists in the cool basement so it would be an easy job to run the pex in the same pipe hangers that the copper is in.
I have the skills and the pex tools so it would be afternoon's work and maybe $60 in parts.
I'm thinking it's worth doing but what says the brain trust here?

How about a circulating pump in the hot water line at the sink farthest from the water heater?...Actually I think it could be anywhere in the line. Maybe a plumber on here could enlighten us tho'

Hot Water Recirculating Pump: What To Know Before You Buy

Tired of waiting for the shower to heat up? Save time, water and money with a hot water recirculating pump.

www.familyhandyman.com

 

[caterpillar guy]

With an insulated line and recirculating pump probably would cost as much as the just running the water till warm. Cost versus cost to make the changes. The time intervals between uses would make more difference for which would be best and cheapest.

 

[ss55]

I replumbed the entire house when I remodeled 12 years ago. Used type M copper pipe throughout.
Some simple arithmetic shows that to get hot water to the kitchen sink - or to a 1/2 bath at that end of the house we are heating 10 lbs of copper pipe each time we wash our hands or rinse a cup.
I am thinking about replacing the copper hot water pipe with Pex. The heat loss would be much less so less energy used, we would get hot water sooner and we'd use less water.
The water lines are exposed and run across the joists in the cool basement so it would be an easy job to run the pex in the same pipe hangers that the copper is in.
I have the skills and the pex tools so it would be afternoon's work and maybe $60 in parts.
I'm thinking it's worth doing but what says the brain trust here

 

[Dusty MI]

How about having a switch on the recirculating pump, and turning it on only when needed?