Need advice / guidance on my upcoming piping remodel.

[joshua5438]

I am getting ready to replace all the failing copper pipes in my house with PEX. I have decided to use Uponor / AquaPEX type A for my install. Just a brief history as to why I am switching over...

I purchased the house in 2015 but the house was originally built in 1980. I was in the house for less than 6 months and had the main water line burst where it enters the crawl space. I have PVC from my well to the house and then they had about one foot of copper pipe thru the foundation wall and then back to PVC to my expansion tank. After the expansion tank it goes to 1/2" copper to the hot water heater and to all other fixtures in the house. The one foot piece of copper is where the pipe burst. Since then I have had five pin hole leaks in the horizontal straight runs under the house. The last leak I had was in the kitchen ceiling (supply line for upstairs bathrooms) at a 90 elbow. A pin hole formed in the solder for the joint.

I currently have two full bathrooms upstairs and one half bathroom downstairs. All three are ran from a single 1/2" copper supply line. I am now wanting to run a separate 3/4" supply line to each bathroom and then branch out to the fixtures with a manifold with 1/2". I am currently planning to do this for both hot and cold unless someone can direct me otherwise. Each 3/4" trunk line will have it's own ball valve under the house so I can isolate each room if the need ever arises.

I have attached a couple of plans I made to help show my current plan of attack. Please let me know if you see anything that needs to be changed or anything you would do differently. I also have a few questions that I have been struggling with and would like to have other opinions. I have listed those questions below also.

1 - Should 3/4" supply lines be used for hot water?
2 - Is 3/4" supply for washing machine unnecessary?
3 - Is 3/4" supply for outside hose bibs unnecessary?
4 - Is 3/4" supply for kitchen sink unnecessary?
5 - Can the dishwasher have it own shutoff valve under the cabinet like the sink or should it be T'ed off from the sink supply line?
6 - Is the dishwasher typically attached to the hot or cold side? I have read contradicting opinions on this one.
7 - In the near future I plan to connect to public water. Should I use 1" or 1 1/4" supply line from the meter to my house? House is about 300 feet from the meter. I may need a booster pump?
8 - A few years from now we are planning to build an addition and will add another full bath in the bonus room. This will be to the left of the master bathroom. So the house will be 3.5 baths. Not sure that this affects anything at this time but maybe it would affect the main supply for public water? Figured it was worth mentioning.
9 - Would I need a larger than 3/4" main supply line in my crawl space once the full bath is added?
10 - I plan to run the supply lines to the upstairs bathrooms with 3/4" and run that all the way to the tub/shower. Then I will use a manifold to branch out to the sinks and toilets. I will have access to these manifold I thought it would be nice to have the only joints in a place that I can access. Is this acceptable?

View attachment Main Level.pdf

View attachment Level 2.pdf

 

[TomFOhio]

You might want to check with your local water supplier and tell them what your plans are and see if you need a 1" line or larger. You can run a 1/2" line off a trunk line to all the fixtures. Yes you can put a valve under the kitchen sink and run 1/2" to the dishwasher. I might suggest you go online and check out the pex manifolds available. There's even some video's. With a manifold you would have a valve and line to each fixture hot and cold. Hope this helps you some.

 

[joshua5438]

Thanks TomFOhio. I have looked at the manifolds online but would rather not pull individual lines to each fixture. That's why I am leaning toward the main trunk line from crawlspace to each room with a small manifold to distribute to each fixture within that room. That's why I was thinking I would go with 3/4" trunk line and then branch out with 1/2" lines. With 3/4" PEX only being slightly larger in diameter than 1/2" Copper I am worried about using 1/2" PEX for my trunk lines.

 

[TomFOhio]

Thanks TomFOhio. I have looked at the manifolds online but would rather not pull individual lines to each fixture. That's why I am leaning toward the main trunk line from crawlspace to each room with a small manifold to distribute to each fixture within that room. That's why I was thinking I would go with 3/4" trunk line and then branch out with 1/2" lines. With 3/4" PEX only being slightly larger in diameter than 1/2" Copper I am worried about using 1/2" PEX for my trunk lines.

Use the 3/4" for your trunk line and then branch off with 1/2" lines to each fixture. You need to run the 3/4" upstairs and then branch off with the 1/2" tubing. If your going to have a 1" main coming into the house you might want to have a 1" trunk line since there will be 3.5 bathrooms. If you run two showers at the same time upstairs the pressure could slow down with a 3/4" trunk line.

 

[joshua5438]

Use the 3/4" for your trunk line and then branch off with 1/2" lines to each fixture. You need to run the 3/4" upstairs and then branch off with the 1/2" tubing. If your going to have a 1" main coming into the house you might want to have a 1" trunk line since there will be 3.5 bathrooms. If you run two showers at the same time upstairs the pressure could slow down with a 3/4" trunk line.

Let me see if I am understanding this correctly...

I should run a 1" main line from water main (once installed) to under the house. continue that 1" main to the water heater and then 1" out of the water heater. Then I can branch off with my 3/4" trunk lines up to the second floor and the branch those out to my fixtures with 1/2". Does that sound right?

 

[TomFOhio]

That is the way I would of suggested to a customer with that many bathrooms. You must have a very large house. The last time I was in a house with that many bathrooms they had two water heaters twinned. You can try it with one first and then see what happens. Can't remember did you say if you had gas or electric water heater.

 

[joshua5438]

The house is about 2500sf. Once the bonus room is finished and the addition to connect the house to the garage it will be close to 3500sf. I currently have electric heat.

 

[TomFOhio]

There's a lot experienced guys on this site. Maybe someone else will get on this thread and give you a second opinion.

 

[joshua5438]

Here is my updated layout.... I still have a few undecided pipe sizes.

1- Trying to decide on 1/2" or 3/4" line for outside hose bibs. Will I really see much of a difference going 3/4"?
2- Still not certain on 1" or 1 1/4" main supply line from the meter to accommodate the future full bath. The tool I will be using for all of the install only goes up to 1". The electric tool is over $800 that does 1 1/4" pipe. Is PEX my best option for the supply line from the meter? I also need to contact the local water company to see what they suggest.

View attachment 1 MAIN LEVEL.pdf

View attachment 1 LEVEL 2.pdf

 

[TomFOhio]

1/2" is plenty for the outside faucets.
Check with your water department and see what they say for the main.
Run a main trunk line and branch off with half inch lines to the faucets. Branch off with three quarter and run upstairs and then take half inch off the three quarter to the faucets upstairs. Pex is a lot cheaper than copper. Its what ever you can afford and comfortable installing. Do you know how to solder copper. You will need to buy a pex tool for the clamps.
Hope this helps you some. Tom...

 

[joshua5438]

Thanks Tom. I have no clue how to solder copper. I have researched PEX and have decided to go with the Uponor fittings with PEX-A. I plan to talk to the water company before I purchase the pipe for the Main to the house. At least I can get the house plumbed without having to worry about the main line. I will just cut the well line once I get the public line installed. I do plan to keep the outside faucets on the well.