House Repipe designing

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by Joseph01, Aug 29, 2020.

  1. Joseph01

    Joseph01 New Member

    Joined:
    Aug 29, 2020
    Location:
    Twin Falls, Idaho
    Warning, I go in-depth and need your help in designing a new affordable system, I would like to hear your suggestions and opinions. The goal of the new system is to reduce noise, insulate pipes, decrease water usage, add a few more water lines for different fixtures, and design a system that will work well for the next 40+ years.

    Pictures of the current system are at the bottom


    Hello, I have been toying with the idea of repiping my house plumbing from the copper pipes installed in 1969 to PEX. I am not a licensed plumber, this would be my first plumbing job, which I intend to have my work up to code. My country follows the IPC book, which I am in the process of reading. I have experience as an apprentice with car repair (finished 13 in-depth restorations in the last year) and was surprised to find out that plumbing wasn't so far off.

    The current copper system is supplied with a 3/4 pipe at 90 psi from the meter (out by the front yard) and serves the trunk and branch system. During winter temperatures outside reach 10 degrees Fahrenheit and below. I will include pictures of the current system and a drawn-out diagram below. The one 3/4 pipe comes into the house and immediately supplies the front hose bibb and then goes towards the back of the house, the main supply pipe splits to go to the rear hose bibb and the kitchen sink, the other pipe it splits to is set up to take a water softener (water softener has since been removed) which is by the HVAC system. The water heater and another cold water line are supplied by the water softener and the bypass pipe. All of the fixtures are in very close proximity to the wall that the pipes are on.

    The current system also suffers from water hammer and makes a ton of noise when water is being used. The pipes are improperly secured which allows them to move around. There have been a few pinhole leaks and the hose bibbs leak and WILL freeze in the winter. My goal is to reduce the water hammer and improve the efficiency of the potable water supply. There are less than 250 feet of copper pipe including hot and cold lines. ALL valves except the Sharkbite 3/4 main shutoff, will not close, there is buildup where water slowly leaked out of the valve stems.

    Currently
    2 Hose bibbs (Located on the same horizontal plane)
    2 Toilets (one upstairs and another downstairs)
    2 Bathroom Sinks (one upstairs and another downstairs)
    1 Kitchen Sink (upstairs)
    1 Sink in the Utility Room(downstairs)
    1 Washing machine (downstairs)


    The design changes
    Switch all of the current pipe from where it enters the house to PEX, get rid of the Sharkbite fittings installed behind drywall during a 2010 basement finishing, not done by me. I want to relocate the water heater about 6 feet closer to a more central location for reduced hot water wait time and add two fixtures. I want to fix the "repairs" done by the previous owner and add a refrigerator ice maker line, water line for a dishwasher, and possibly water lines for a sprinkler system. Most of my work would be done in the Utility Room which is unfinished and easy to access. The room would be finished after the plumbing was done and the proper permits acquired.

    I want to use a trunk and branch system, seeing as using the other two main designs would not be a benefit with everything so close. I would like to add a pressure reducing valve, expansion tank, new (or rebuild the current 20 year old) water heater as well as bracing the water heater for earthquake protection. I would like to use PEX with minimized crimp connections as well as insulate the pipes which would further help with noise and keeping water warmer for a longer length of time.

    I plan on drawing up a "rough draft" of what the new system would look like within the next day. Based on the pictures and sketches, as well as all of your experience, what do you think about it, how would you do the work and what should I watch out for? I plan on cutting out sections of drywall to more easily access the pipe hidden in the basement ceiling and downstairs bathroom.

    Thank you for your time, patience, and help!!

    I plan on posting some more information tomorrow, it's pretty late as I'm typing this

    20200829_221537.jpg 20200829_221545.jpg 20200829_221551.jpg 20200829_221559.jpg 20200829_221615.jpg 20200829_221939.jpg 20200829_221537.jpg 20200829_221545.jpg 20200829_221551.jpg 20200829_221559.jpg 20200829_221615.jpg 20200829_221939.jpg

    These drawings are the current hot and cold water pipes as well as the utility room basic floor plan

    20200829_225411.jpg 20200829_225802.jpg 20200829_230248.jpg
     
  2. Terry H

    Terry H In the Trades

    Joined:
    Aug 4, 2020
    Location:
    Alabama
    The water hammer could be from a few things but the high pressure doesn’t help and could be the source altogether.

    I’d recommend uponor or rehau piping but if you’re willing to buy uponor tool for their fittings you will be happy. Their system does not restrict flow and the piping can be bent with or without bend supports depending how sharp of a bend.

    Frost proof hose bibs or have a way to drain them down when not in use.

    I would put a new water heater since you’ll have new pipes and don’t want to put the junk in the heater in your new lines. As far as having to wait on hot water you could look into a recirculating setup while you’re piping the home or they even have one now where you put a fitting under the sink in the bathroom and that allows the pump to recirculate.
     
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  4. Jeff H Young

    Jeff H Young In the Trades

    Joined:
    Feb 27, 2020
    Location:
    92346
    I would start out with 1 inch pipe. absolutly be adding presure reducing valve. you also need to figure on freezing pipes w frostproof silcocks to fit your needs. havent really studyed your plan out. but get past a few tees befor breaking down to 3/4.
     
  5. Helper Dave

    Helper Dave In the Trades

    Joined:
    May 25, 2020
    Location:
    Wisconsin
    I agree with the other comments so far. Another point to add, just make sure you run 3/4 to just before teeing off for the toilets. Kinda a must when using PEX.
     
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  6. Jeff H Young

    Jeff H Young In the Trades

    Joined:
    Feb 27, 2020
    Location:
    92346
    BTW, 51 years and still going not a bad testimony for copper, most likely type m (i dont find L often in old homes)
    40 or 50 years from now I wont be doing repipes Im wondering how buisness will be when these houses have 50 years on pex or cpvc
     
  7. Joseph01

    Joseph01 New Member

    Joined:
    Aug 29, 2020
    Location:
    Twin Falls, Idaho

    My house water meter located out on the lawn is buried several feet below ground, underneath the freeze line, the supply pipe also goes beneath the concrete and a front deck. My main concern with switching over to 1" is that it doesn't do much good unless it is 1" from the meter to the house, and to dig the trench, it is easier for the first 10 feet but I'll have about 1.5 feet of working room beneath the deck for the last 10 to 15 feet. So, difficult yes, but not impossible. The house would benefit from a 1" line, it just adds time and labor to the job. I will consider doing this upgrade when I've decided that its time to run the irrigation system within the next month or early next year.

    As for your comment about not planning everything out, I just have not gone in-depth with my first comment. I've also asked for help to make sure that everything is up to code and someone who has had experience with plumbing will know what works and what won't. As I stated before, this will be my first plumbing job. I am by no means a professional or expert. I do plan on getting permits for the repipe and irrigation system. Part of my motivation to do the plumbing is when we had a pinhole leak and called in a local plumber to fix it and were charged 300

    I'm still developing the new plan, but my idea is to start off by getting rid of the 3/4 inch Sharkbite 90 degree elbow, 3/4 inch Sharkbite coupling, and the 3/4 inch Sharkbite ball valve and replace that with soldered joints instead and a threaded 3/4 inch ball valve with a copper to pex adapter. As seen in the sketch, the main supply line goes through the ceiling into the living room. I will be cutting ports in the drywall to mount the pipe properly, every 32". The main line goes into the utility room behind the HVAC ducts and will go into a pressure reducing valve located where it is easily accessible. A water filter will be placed after the valve, the pipe will spilt into two 3/4 inch lines, one that goes to a water softener (which will be located where the water heater currently is), and another pipe that has unsoftened water supplying a future automated irrigation system, the frost-free hose silcocks located at the front and back of the house as well as the refrigerator ice maker line. The softened water line will go through the wall. I am going to build a new, compact vanity for the utility sink downstairs, which will provide more room for the water heater to be placed next to it.

    The irrigation system would be run at night so it would not interfere with pressure when people are using water during the daytime.
    I may also run the irrigation more traditionally by tapping into the 3/4 inch line after the water meter and installing necessary hardware (backflow prevention device, water filter, water pressure reducer valve) for more reliable pressure, instead of going into the house and back out to the yard which would reduce pressure.



    As for the softened cold water line, I will be using 3/4 inch and 1/2 inch to supply the fixtures.

    The water heater will be supplied with 3/4 inch softened water, however, all hot water lines will be supplied with 3/4 PEX until there are two fixtures, I plan to switch to 1/2 inch pipe to the fixtures. One of my goals is to reduce wait time for hot water and decrease the amount of water that is purged from the line each time. I will not be adding a hot water circulation loop mainly due to the cost and close proximity of the fixtures to the water heater. Current hot water wait times will stay the same (as the current system) or be reduced from current times. The longest wait time is for the downstairs bathroom sink which is located furthest away, with the hot water valve open fully, it takes exactly 15.4 seconds to have hot water to the fixture.

    Thanks for your time and help.
     
  8. Jeff H Young

    Jeff H Young In the Trades

    Joined:
    Feb 27, 2020
    Location:
    92346
    Joseph, comment about your plan was that I hadent taken the time to figure it all out. You put a lot of info out which is good, Ill be re reading it all its a lot there to grasp it all.
    I will give some general Idea and opinion but dont think Ill be figuring out the entire system.
    I dont get it running 3/4 in a ditch much easier than 1 inch? ok run 3/4 then or dont repipe that section .
    You have 90 psi install prv at main entering house and at that point increase to 1 inch. True it wont help that much running 1 inch here , the water will travel at less feet per second resulting in less friction, and less pressure drop, and less water hammer and strain on system . Going way oversize on pipe wastes money and time going barely over the minimum allowed by code Wastes money and time as well if its a flip house, and even still might not make a differance in the short run. but minor tweaks to desighn I think make worthwhile differances and add to a better system. Running oversize on your hot water will cause longer wait times for hot water to arrive at fixture some things to concider
     
  9. Joseph01

    Joseph01 New Member

    Joined:
    Aug 29, 2020
    Location:
    Twin Falls, Idaho
    I'll post more as I am able to but here is a potential System. Let me know what needs to be changed. I did not include ball valves in this picture. Just getting my ideas out onto paper. 20200830_111843.jpg
     
  10. wwhitney

    wwhitney Well-Known Member

    Joined:
    Mar 17, 2019
    Location:
    Berkeley, CA
    So, that's probably not true. You'll have the losses from the pipe size connecting the water main to the meter to the house. If that distance is the same order of magnitude as the distances you're running inside the house, you'll see some benefit from upsizing the pipe in the house. If you're 1000' from the water main, and just talking about 50' of pipe within your house, then certainly it won't do much good.

    You can think of it as (non-linear) resistors in series. You can't avoid the upstream resistance, but reducing the downstream resistance (pressure loss) still decreases the total resistance.

    Cheers, Wayne
     
  11. Joseph01

    Joseph01 New Member

    Joined:
    Aug 29, 2020
    Location:
    Twin Falls, Idaho
    Ok, here is an update. I have been redesigning the water supply. I wasn't happy with the water heater being on a line that served other fixtures, so I have given the water heater its own separate line. I have been watching water pressure every day for the past week and here are the results, 90psi, 70psi, 75spi, 75psi, 75psi, 83psi, and 61psi from the city.

    I will be posting an updated design when I can. I do have the go-ahead to run pipes for a lawn irrigation system though so that will be factored into the design.

    Thanks for your time, Joseph
     
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