PVC in the North

[cenlo]

I keep reading about using poly in the Northern climates and pvc in the Southern. I don't understand why? If all the water can be blown out of the lines prior to the first frost then whats the problem? Please advise? I am going to be using a mini trencher (I no, it's not as good as a plow) and laying 3/4" - 1" pvc mains. Most applications are 4-6 zone properties. I thought with the 3/4" mains, they would still offer some flex.

Thanks in advance, Cenlo

[Broker]

The Poly is better for the annual freeze and thaw. I fix broken PVC lines every year to to freeze damage. We don't install PVC on Residentials in northern Ohio but if you are stuck on it because it is easier to use in an open trench then it gives you that much more job security as some people might say. I know that it is cheaper overall to install then poly too.

[cenlo]

I fix broken PVC lines every year to to freeze damage.

Are they damaged by ground shifts of by poor blow-outs?

[Broker]

They are damaged because PVC becomes brittle at a faster rate then poly, as the system gets older the integrity of the pipe is weakened. I could say the the blowouts might not have been done correct but in the same breath I could say if the winterization is not done correct for a PVC & Poly system you are more likely to have freeze damage on a PVC system. Most of the repairs we make on other systems with PVC are lateral too not just main. Every system should always have a PVC main, because you should never have poly under constant pressure. Remember that all of this stuff that I am telling you is just what I have learned through the years from experience, suppliers and the IA. So I could be wrong & take it for what it is worth. It seems like what ever type of system someone was trained on have it be PVC or Poly it is what they will stick with. Email the IA if you want a technical answer with data to back it up.

[cenlo]

Most of the repairs we make on other systems with PVC are lateral too not just main. Every system should always have a PVC main, because you should never have poly under constant pressure.

I was planning on (for most jobs) 1" pvc to the valves and then 3/4" pvc for the zone mains. From there I would use 1/2" "funny pipe" to the heads. Would that make a difference?

[Wet_Boots]

Stick with poly pipe in colder climates, and you will have happier customers. PVC gets brittle with cold and age. and the shifting of the soil from frost and heave can fracture PVC. And unlike a small split in a poly line, when and if it should ever develop a leak, a PVC pipe can split for an entire 20 foot length. Digging up 20-odd feet of your customer's lawn will not make you their favorite person.

[JeffY]

I use PVC to valves and poly afterwards. I too have come across busted PVC during sprinkler turn-ons due to freeze damage/brittle PVC. If you're going to use PVC throughout the whole system, I would use 1" to your valves like you said, and then 1" to your zone mains. You can then step down to 3/4 after that. The whole purpose is to maximize your flow and pressure efficiently. If you step down to 3/4 right after the valves, you will lose suffer greater pressure loss at the furthest head. With the funny pipe, you should limit it to 6' and 1 head.

[cenlo]

Is there any other piping in 20' lenghts that would be better? Or how can I straighten the poly to keep it in the trench? Thanks, Cenlo

[Wet_Boots]

You buy poly pipe in big rolls, like 300 feet (or maybe 100 meters) for one inch poly, and use a vibratory plow to pull it without trenching. If you see a good how-to page on poly pipe in a trench, the straightness is not only unimportant, you will see advice to have the pipe snake from side to side in a trench. This is because the pipe can shrink a bit when it gets colder in the winter. (despite that shrinkage, it doesn't often affect systems with poly pipe pulled in straight lines by a plow)

[cenlo]

You buy poly pipe in big rolls, like 300 feet (or maybe 100 meters) for one inch poly, and use a vibratory plow to pull it without trenching.

I understand poly pipe comes in rolls. I can't pull it with a vibe plow because I will be using a mini trencher. The poly rolls are about 48" - 60" dia. I imagine that when it is 50 deg. outside in the morning it is not going to lay in the trench very well!

[JeffY]

The poly isn't going to want to lay down in a trench for long since it will want to coil up. The only way to prevent it is to dump dirt on the line near the beginning where a connection is not needed to keep the pipe in the trench and roll out the poly to the end of the trench, cut it, and dump dirt near that as well. If anyone can find a way to straighten poly, let me know...

[Wet_Boots]

No equipment rental, or far better, I suspect, a subcontractor to handle the vibratory plow work? Nothing you can do will beat watching this essential aspect of the job being done with the right equipment. The time saved versus the money spent makes it a no-brainer.

[Rotor-Man]

As far as straighting poly pipe to pull with a sneaker, it can be done and I usually pull poly in all by myself. I just basically use all 100' coils and stick it in the chinese fingers and walk it backwards and it will lay flat and straight, especially in the middle of the summer when it is warm.

[GrazerZ]

1" poly is not too bad to work with. you could lay it out in the sun and then spot fill the trench to keep it down in the trench. working with bigger than 1" would be very challenging though.

[cenlo]

No equipment rental, or far better, I suspect, a subcontractor to handle the vibratory plow work? Nothing you can do will beat watching this essential aspect of the job being done with the right equipment. The time saved versus the money spent makes it a no-brainer.

No rental equipment here! Also, only two people pull pipe here but are major competition and would never help out. Is there any advantage to the customer by having a mini trnch? (maybe they will like the mess) :)

[cenlo]

All golf courses and commercial jobs use pvc around here so why is the pvc used there? I assume due to the constant increased pressure. Wouldn't the pipe still be damaged the same?

[DanaMac]

Commercial jobs typically will be maintained better and more often than a residential system. In residential you are relying on the homeowners to make the decision on whether they want to pay to have it blown out. They always think "oh it will drain just fine", "it won't get that cold". But commercial projects either have contracts with irrigation companies or lawn maintenance to take care of this. Homeowners are always going to balk at paying to have it done - until they get a major bill in the spring to fix the freeze damage.

My worst freeze damage repair was the first year I was a repair technician. This system had been in 20 years and had auto drains, which worked fine up until this one year. there was a leak in the yard so I dug it up. It ended up that the 1 1/4" PVC had shattered 60' (yes 60'), and it was the bottom pipe in a trench with 4 other pipes. The auto drain apparently failed. It shattered thru 3 glue joints as well to get the 60'.

[cenlo]

My worst freeze damage repair was the first year I was a repair technician. This system had been in 20 years and had auto drains, which worked fine up until this one year. there was a leak in the yard so I dug it up. It ended up that the 1 1/4" PVC had shattered 60' (yes 60'), and it was the bottom pipe in a trench with 4 other pipes.

Do you think then that if a pvc system is blown out properly in a cold climate there should be no problems?

[Grassmechanic]

There is nothing wrong with PVC piping in cold locations. PVC is the standard for golf course and commercial applications. Every golf course (and there are a lot of them) in MI has PVC piping. Regardless of poly or PVC, the systems need to be correctly winterized in freezing climates.

[Wet_Boots]

Larger industrial sprinkler systems and golf course systems are a thing apart from the residential jobs I believe you are interested in. In those big jobs, you will often see larger sizes of PVC used, often joined with gasketed fittings, and braced with thrust blocks. The trenches will be backfilled with sand around and over the pipe, which serves to protect the pipe from soil shifts. You cannot easily do anything comparable for a residential job.

As for equipment, I see that you could be better located, but you are not entirely deserted. There seems to be a Case dealer (<a href=http://www.bmcdowell.com/>McDowell</a>) in Sudbury, so a Mini-Sneaker or Maxi-Sneaker could probably get maintenance. For Vermeer and Ditch-Witch, taking distance into account, it seems you have to look at dealers in the States.

As for a properly-blown-out system being immune from freezing problems, don't count on it. You do know that ball valves sometimes fail to shut off 100 percent, don't you? Better plan for leaking water to safely drip out of the piping during winter. Frost and heave can do damage on its own, and any forces that tree roots may exert over the years of their growth could also do damage. I take specific note of tree roots, because one positive result of using Schedule 40 PVC in place of poly pipe is that the occasional strangulation of poly pipe by tree roots isn't suffered by PVC to the same extent. Thinner-walled SDR-21 or SDR-26 won't be as strong in this regard.

If you do anticipate a future of installing irrigation, I believe you will get a vibratory plow. It's not a matter of if, but when. Plan for it in your budgeting.

[Broker]

There is nothing wrong with PVC piping in cold locations. PVC is the standard for golf course and commercial applications. Every golf course (and there are a lot of them) in MI has PVC piping. Regardless of poly or PVC, the systems need to be correctly winterized in freezing climates.

I am not sure how you guys do it in your area. But there is a wee bit of a difference in a Golf Course install vs. Residential. Here in Cleveland your typical residential is installed 6-12" deep (frost line is 18") a golf course laterals and mains are 3' or 36" deep (frost line is once again 18") plus I have yet to see poly in 2,4 & 6" in size. Commercial installs are typically PVC main with poly laterals with the main 18-24" deep depending on the spec. Remember the thread was concerning small 4-6 zone residentials.

[Broker]

Larger industrial sprinkler systems and golf course systems are a thing apart from the residential jobs I believe you are interested in. In those big jobs, you will often see larger sizes of PVC used, often joined with gasketed fittings, and braced with thrust blocks. The trenches will be backfilled with sand around and over the pipe, which serves to protect the pipe from soil shifts. You cannot easily do anything comparable for a residential job.

As for equipment, I see that you could be better located, but you are not entirely deserted. There seems to be a Case dealer (<a href=http://www.bmcdowell.com/>McDowell</a>) in Sudbury, so a Mini-Sneaker or Maxi-Sneaker could probably get maintenance. For Vermeer and Ditch-Witch, taking distance into account, it seems you have to look at dealers in the States.

As for a properly-blown-out system being immune from freezing problems, don't count on it. You do know that ball valves sometimes fail to shut off 100 percent, don't you? Better plan for leaking water to safely drip out of the piping during winter. Frost and heave can do damage on its own, and any forces that tree roots may exert over the years of their growth could also do damage. I take specific note of tree roots, because one positive result of using Schedule 40 PVC in place of poly pipe is that the occasional strangulation of poly pipe by tree roots isn't suffered by PVC to the same extent. Thinner-walled SDR-21 or SDR-26 won't be as strong in this regard.

If you do anticipate a future of installing irrigation, I believe you will get a vibratory plow. It's not a matter of if, but when. Plan for it in your budgeting.

Ball Valves not shutting off 100%, tell me about it. That sucks it usually takes us two start-ups to shoot that unless we see enough water during the first one to warrant having it tested.

[Grassmechanic]

I am not sure how you guys do it in your area. But there is a wee bit of a difference in a Golf Course install vs. Residential. Here in Cleveland your typical residential is installed 6-12" deep (frost line is 18") a golf course laterals and mains are 3' or 36" deep (frost line is once again 18") plus I have yet to see poly in 2,4 & 6" in size. Commercial installs are typically PVC main with poly laterals with the main 18-24" deep depending on the spec. Remember the thread was concerning small 4-6 zone residentials.
I stand by my comments. I have manyyyyy more years experience with golf course (up to 16" SCH80) and commercial irrigation than I care to count. My frost line is 42". Poly/PVC, doesn't matter what you use, it still needs to be correctly winterized.

[Broker]

I stand by my comments. I have manyyyyy more years experience with golf course (up to 16" SCH80) and commercial irrigation than I care to count. My frost line is 42". Poly/PVC, doesn't matter what you use, it still needs to be correctly winterized.

Not new to the business, any yahoo knows it needs to be correctly winterized. Where do you live the U.P.?? What was you gpm on 16" around here 6" is usually the max. It was a golf course app? What brand do you like for golf course?

[cenlo]

As for a properly-blown-out system being immune from freezing problems, don't count on it. You do know that ball valves sometimes fail to shut off 100 percent, don't you? Better plan for leaking water to safely drip out of the piping during winter.

I,m sure that could be eliminated with a double ball valve. Close the first and open the second as an exterior drain. (which should never work).

If you were starting out what would be the most inexpensive puller to buy. (Keep in mind all properties are small)

Thanks,..again :)

BTW I'm not trying to be a "pain in the ******", just looking for some advice. I appreciate it all!

[Georgia Bull Dog]

Use poly , put a you can straighten it with a torch. PVC for large commercial installs. If you are serious about irrigation get a vib.Plow.
Noel

[Grassmechanic]

Not new to the business, any yahoo knows it needs to be correctly winterized. Where do you live the U.P.?? What was you gpm on 16" around here 6" is usually the max. It was a golf course app? What brand do you like for golf course?

GPM was around 1500 @ 125PSI. Almost 1/4 mile of main, all glued belled pipe. 16" about half of it, then reduced to 12". The laterals down the fairways were 6" and 3", depending on how far they were from the pumphouse. The heads all had 1 1/2" swing joints going to them. All pipe was sch80, including swing joints. The pipe manufacturer was Crestline, if I'm not mistaken.

[Broker]

GPM was around 1500 @ 125PSI. Almost 1/4 mile of main, all glued belled pipe. 16" about half of it, then reduced to 12". The laterals down the fairways were 6" and 3", depending on how far they were from the pumphouse. The heads all had 1 1/2" swing joints going to them. All pipe was sch80, including swing joints. The pipe manufacturer was Crestline, if I'm not mistaken.

Pretty damn impressive.

[Grassmechanic]

Pretty damn impressive.

Actually, it's a pretty typical set up. I've seen much larger ones, utilizing a pair of 100hp pumps and 25 hp jockey pumps, all 480volt three phase set ups. I'd hate to pay that electric bill. payup