# PVC CL200 or SCH 40 vs Poly Pipe



## psider25 (May 4, 2020)

OK ....looking for feedback, opinions, and lessons learned from past history regarding what preference is out there for choice of pipe material.

I am interested primarily in feedback from those in freezing climates who will have to winterize their system every year.

PVC - CL200 (SDR-21) - most economical, best GPM/psi loss per outside diameter // 200 psi pressure rating seems like plenty, but is there any concern for durability if you plan to own the property for a long time

PVC - SCH 40 - Is it worth the extra cost? any downsides vs CL200 other than less GPM and more psi loss per outside diameter? Will it really provide more durability in the long run?

Poly - Is it really resistant to cold, and worth the hassle of all the fitting, clamps, etc? Is it hard to source locally as it seems and the pros have switched to PVC (CL200) (at least in my area)?


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## psider25 (May 4, 2020)

Forgot to include link to nice table for PSI Loss and Velocity per GPM Flow for various pipe types and diameters

https://www.sprinklerwarehouse.com/v/vspfiles/manuals/charts/friction_loss.pdf


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## TSGarp007 (May 22, 2018)

I think the schedule 40 is more durable from the standpoint of shovels, etc. But that's the only benefit I know of. I think it it's buried and protected it will last a really long time. I made some repairs to my old zones and the class pipe broke when I tried to use pipe cutters on it, so I had to use a hacksaw. But I can't remember if it was class 200 or 125... I've cut new 200 pipe with my cutters no problem.

I think based on your location the more important thing is getting anything that is under constant pressure below your frost line? Might be a reason to use that master valve so your piping around the house doesn't have to be so deep, assuming it will be winterized prior to first frost.

Maybe some more experienced posters will chime in, but I'm sure you'd be fine with the class 200.


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## g-man (Jun 15, 2017)

We have frost heaves. The stronger the pipe the better to avoid cracks when the soil moves. But s poly pipe is strong but more flexible than pvc. I prefer poly rated for above 125psi.

There is another benefit from poly. You buy it is long rolls that allow you to do runs without unions. Pvc in 10ft, you have to glue it. Both works, but I prefer poly.


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## psider25 (May 4, 2020)

@TSGarp007 @g-man Thanks for the replies.

All the residential irrigation companies around here use CL200 and pull it in with a vibratory plow about 10 inches deep even for main lines. The irrigation supply place wants me to use 20 ft CL200 PVC. My neighbor recommends poly.

My neighbor who has lived here forever installed poly in his yard and said at one point the city banned it and required commercial guys to all use PVC ..said poly cannot be pressure certified. But then it was repealed later somehow?, however irrigation companies still use PVC and that is what the supply houses stock. My neighbor says he would never use PVC ...but I have not really heard of people who had professional installs having issues with it (as long as they winterize it).

I think with our clay soil here and winters that get down below 0 degF for at least a small part of the winter most years there is probably soil movement at 10 inches down.

@g-man Are the connections prone to failure with the poly? It looks like all that is holding them on is some barb fittings and a metal pipe clamp. Every time I have dug up a pipe with a metal pipe clamp in the past the screw mechanism no longer works. Does the poly connect to the valves with barb fittings as well?

Thanks again for all the help. This has been fun learning about all the mechanics.


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## tommyboy (Aug 20, 2019)

I used poly in southern WI . 15 years and no issues. 15" down. Frost line here is about 4'.


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## Thick n Dense (May 7, 2019)

@g-man

What connections do you use for your poly pipe ? 
Been debating this too...

I'm thinking that Pvc will be faster than messing around with the blue connectors, could be wrong though.

Will PVc survive a winter above ground if properly winterized?


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## Pete1313 (May 3, 2017)

Most of my main lines are sch 40 PVC that was buried below the frost line by the original owner 28 years ago. I wouldn't have done it that way, but there is something to be said about it as they are still holding strong. Repairs would be fun though, what happens if they spring a leak. When I rehabbed the irrigation in 2017 all my lateral work was done with poly. No issues, buried around 9-10" deep. Poly is alot easier to work with and all the fittings, crimp clamps and pipe were easily sourced at my local menards. If I would have designed the whole system, it all would have been 9-10" deep. I might have still used sch 40 for the mains to the valves, or at least include a master valve near the house.


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## g-man (Jun 15, 2017)

PVC above ground exposed to uv does degrade it over time.

I use the Menards poly connectors like this https://www.menards.com/main/plumbing/pipe-fittings/polypipe/lasco-reg-pvc-poly-pipe-barbed-insert-tee/1401005rmc/p-552765097604599-c-8570.htm


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## Pete1313 (May 3, 2017)

g-man said:


> PVC above ground exposed to uv does degrade it over time.
> 
> I use the Menards poly connectors like this https://www.menards.com/main/plumbing/pipe-fittings/polypipe/lasco-reg-pvc-poly-pipe-barbed-insert-tee/1401005rmc/p-552765097604599-c-8570.htm


Same ones here as well. :thumbsup:


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## Utk03analyst (Jun 8, 2019)

I went with poly on everything but my main lines. Agree with the comment about the long runs but you can buy pvc from irrigation supply stores in 20 foot runs that are flared on one end so you don't have to add a connector just glue the two 20 foot lines together. I personally would rather just heat and clamp poly all day long versus gluing pvc. There are regular crimp type fittings for poly that you can use a nail puller to crimp. Just don't overheat your pipe.


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