# Extending basement water line outside



## DavidJ726 (Jul 1, 2021)

Hi all,

I'm a new user here, and am looking for a few tips...

I have a contractor installing a sprinkler system in the back yard for me, and wants to tap into the 3/4 waterline in my basement as opposed to trenching and installing a line to the front yard where the city water main is. To save a few dollars, I agreed to stub the line out for him.

I think I know what I need for inside, but I'm not sure what I need to make sure the stubbed pipe is secure on the outside wall. An outdoor faucet has a flange to screw it down to the wall, but I can't find anything like that for a loose pipe. The only thing I can think of, is to put an elbow on the pipe and then secure it to the wall with a pipe strap. Is there any other options I'm not thinking of?

Also, he doesn't care if I use a Poly or copper pipe for the stub. I'm concerned about UV on the poly, but is that a valid option?

And should I consider some sort of enclosure for the pipe where it comes out of the wall? He is adding a ball valve outdoors, but no backflow valve since it's not required here.

Thanks,

David


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## Mocajoe (Apr 9, 2018)

Welcome to the forum. My sprinkler system and hose bibs are all run on 3/4 copper lines. Be sure to install a 3/4 shutoff valve with a drain inside to protect from freezing temperatures and allow you to drain the system. My concern with securing the lines going through the wall was more for the hose bibs which tend to get tugged on when using the hoses. I used grounding clamps to secure the hose bibs. The line feeding my back flow valve is not secured but has never been an issue.


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## LeeB (Jul 1, 2019)

I think you need the backflow, there are pretty much required on any city water system nowadays. Kansas Administrative Regulations Section 28-15-18 (f) states:



> Each person that operates a community water supply system and each person that operates a high-risk non-community system designed by the department shall have a regular program for the detection and elimination of cross-connections and prevention of backflow and backsiphonage.


Call your water dept and ask.

You definitely need to put a ball valve INSIDE as your shutoff so it doesn't freeze. Slope your stub slightly downwards going through the wall to outside, and add a tee with a drain valve so the system can be drained and blown in the fall. To strap pipe you can use pipe hangers with threaded rod, or add a piece of wood with a bell hanger between your joists where it goes through. I would just strap it outside though by the backflow.

Here's how the outside should be done. Notice the pipe hanger in the back.









Definitely use 3/4 copper because PEX has lower flow for the same size. You could use 1" pex.


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## DavidJ726 (Jul 1, 2021)

Hi Mocajoe, thanks for the tip! Those clamps are a great idea and probably what I'll end up using.

David


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## DavidJ726 (Jul 1, 2021)

LeeB,

Thanks for clarifying the Kansas code, and for the photo, that helps a lot!

Edit: It appears that you have 2 fitting to blow out the line? If so, why 2?


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## LeeB (Jul 1, 2019)

DavidJ726 said:


> LeeB,
> 
> Thanks for clarifying the Kansas code, and for the photo, that helps a lot!
> 
> Edit: It appears that you have 2 fitting to blow out the line? If so, why 2?


If you are talking about the two things with the black caps, those are the pressure test cocks for testing the back-flow preventer, they are too small for air blowout. You would hook the air up to the drain hose bib (or remove it and go right into the tee with a 1/2" NPT adapter).

Also, the backflow device need to be located higher than any of the sprinkler heads. So if you have sprinklers going uphill from the stub-out location you need to raise up the backflow on the wall until it's at a higher elevation than any of the heads on the hill.


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## DavidJ726 (Jul 1, 2021)

Thanks LeeB, yes, the black caps is what I assumed was a blow out.

The yard slopes away from the house so I'm good there.


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