Pole barn drainage - need some advice

[DrewStyduhar]

Hello everyone,

I have a 40x50 metal roof pole barn that has gutters and I'm temporarily using corrugated pipe from the downspouts to get water away from the building. Time has come to trench and bury some pipe and was hoping to get an opinion on what to do here. I made a quick pic in paint to show what I'm trying to accomplish. Basically the plan is to dig a ~50 foot long trench 3' from the building and tie the gable downspouts together and daylight everything out behind the building. I also plan to add a trench drain in front of the overhead door openings in the future and want to connect those in with the pipes on each side of the barn. It will look like a big "U". Also, pretty sure the gutters are 5" gutter with 3x4" downspouts.

Some questions:

- What type/size of pipe would you use for orange in pic? Im thinking schedule 40 pvc 4" but im worried the 4" might not be big enough when I add the trench drain. 6"? I also thought about schedule 20 but its possible I might be driving my tractor over where the pipe is buried so sort of nervous about thin wall stuff. Dont want to fool with corruguated stuff for this.

- Should the pvc pipe be solid or perforated? I figured the perf pipe was to deal with wet areas but I'm just trying to dispose of the roof runoff. The barn isnt down in a hole or anything. It is on a grade with the high side in FRONT but its such a mild grade im not real worried about it.

- I was reading where some guys say dont glue the 10' sections of pipe, others say glue it. I planned to glue it (why not?) but figured I would throw that out there.

thanks in advance for any advice or ideas

Drew

 

[jaxs]

I'm sure you will get a bunch of detailed specs based on wigs and wags but here's my thoughts. Use gutter downspouts from gutter to drain line and uv resistant material for above ground fittings. Electrical conduit is suitable for continuos exposure to sun. 4" will carry the load except during floods, fittings and pipe are half the price of 6", easy to find if repairs are needed down the road so 4" it is. To add volocity, I suggest wye fittings rather than tees where downspouts enter lines. If down spouts aren't easy to disconnect,install clean-outs. If alot of leaves and debris fall's on roof,that's your call because there are countless systems,some good,some near worthless.

 

[Spike56]

I have some experience with your project. However, my initial disclaimer is " I am not an expert" .
The first thing that jumped out for me is your question: "Should the pvc pipe be solid or perforated?" I would absolutely NOT use perforated pipe. As the water flows thru, especially when it slows down, it will pull dirt / debris from the holes into the pipe. Add to that, any nearby roots will find a home in the moist soil and grow into the pipe. Bigtime mess / re-work.
Why not glue the pipe ? No idea why anyone would say not to ? Although PVC joints "should" remain connected without glue assuming carefully buried, I would be concerned about the ground shifting / roots - as in old clay tile sewer pipe.
For 40x50 (2000sq/ft) : so round numbers (a 1" rain will be about 1200 gallons). This makes is a little difficult to decide what size and how to construct. Obviously, the rain amount and rate makes a big difference. My only advice is to OVER DO IT. Your drawing has part of the trench and (2) gutters into one pipe. In my opinion, THE thing to be most concerned about is preventing the gutters from overflowing. The weight of the water (unless you have very strong gutters) will bend / deform them. So, If it were me, I would at least use a 4" pipe per gutter.

 

[Dwellonroof]

I've been installing gutter and drainage for over 40 years but in reality you only need a solid 4" and only on one side of the building.

 

[LD1]

The unknown variable in your equation is how much runoff and flow is expected in the trench drain that you want to tie in?

The barn is easy to figure. Because we know its dimensions....and ONLY the rain that falls on said dimension will enter this system. But the trench drain......is it just a low spot draining ~1000 sq ft of surface runoff? Or is this shop at the bottom of a hill and 3 acres worth of water are gonna want to pond there?

Asuming you are accounting for minimal out of the surface drain.....I'd run 4" from the drain, wye in the downspout and keep it at 4 for the width of the building. When you pick up the last downspout, jump to 6.

I also wouldt fool with PVC. I'd do black corrugated. ANd if you are worried about where it daylights and not crushing it, a sitck of corrugated double wall on the ends.

I put in thousands of feet of drainage tile per year. The black corrugated is by far the most cost effective, and at the end of the day it does the same thing. ~$0.40 per ft for 4" and about $1.00 for 6". PVC, even the light weight stuff is 3x the cost

 

[EddieWalker]

Don't worry about Typhoons or extreme weather. You'll never have enough drainage for extreme weather. 4 inch will handle 99 percent of what comes off the roof. Anything else will just overflow your gutters and end up where the rest of the rain is falling on the ground.

In my opinion, corrugated drain pipe is fine for gutters. It's cheap and it lasts forever. I would not worry about the ribs inside the pipe. Water will flow through it just fine.

I've never seen thin wall pipe last. It gets brittle in the ground.

If you want the best, do it like a septic system and use SDR35. Lowes sells 4inch sticks that are 10 feet long for a little over $16 each. Nothing is better for drain lines. But then you will spend a fortune on your corners and T's or Y's. I use Schedule 40 for those with the adapters, which really adds up. But that was for my septic system, not my gutters.

For my own house, I used 4 inch corrugated. It's been 16 years and they are still working great. When I add on next year, I'll stick with 4 inch corrugated pipe for my gutters.

 

[dirttoys]

I wrestle with water everyday. That doesn't make me an expert (in fact if I was better maybe I would fight it less).

Are there any trees, looking at the drawing I don't see where the leaves get picked off?

Best,

ed

 

[DrewStyduhar]

Wow, a ton of info here. I updated the picture to show adjacent trees. There is a pine stand behind the building, maybe 40 feet or so. And there is a white oak about 75 feet from the corner of the building.

I checked the price on 4" vs 6" pipe/fittings and didnt realize the difference was so massive. I plan to make the connection from downspout to wye using a short piece of corrugated so I think it would be easy to snake out if it gets plugged. I havent made up my mind on the gutter guards yet.


I just want to use whatever pipe is best for drainage. I am digging through super compacted sandrock by hand and it's terrible. I dont want to do this again, haha.

The trench drain wont see a lot of water. Its not to drain any sort of wet area.

thanks,

Drew

 

[Dwellonroof]

I sure wouldn't use the corrugated stuff but schedule 35 at the minimum.
You can put a micromesh screen in your gutters to keep from clogging.

 

[Rockbadchild]

I have heard the ripples in corrugated pipe or a culvert for this matter helps clearing and or minimizing sediment accumulation, I have learn at schools that ripples help increasing the flow inside a pipe and at the contradictory I have heard smooth plastic was better to minimize sediment and easier to clean but I am not sure, seen some contractor swearing one and condemning the other and the next one doing the exact opposite … its muddy water id say at best … both have positive and negative guess … if you are going to drive over it I would do rigid if not id do corrugated with the membrane … a nice base of pure stone would help with flow … for pvc glued or not I don't see any advantage personally I leave it up to you but personally wouldn't. … 4 inch should be sufficient especially if you have a couple if inch of pure stone as a base. Screen caps for all daylight ends for sure.

 

[DrewStyduhar]

Just FYI, the gutters on each eve are sloped so they are high in the middle. So although each orange pipe is tied to both gutters its prob only getting half or so unless the weather really goes nuts. I like LD1's idea of jumping to 6 at the back of the building. Would save on fittings costs too vs going 6" along both sides.

thanks,

Drew

 

[LD1]

Not sure why so many people dont like black corrugated pipe.

ITS MADE FOR DRAINAGE.

There are hundreds of thousands of miles of the stuff in the ground all around me for ag drainage. As is smoothwall old clay.

Guess what, if there are problems they both plug up. But if its installed right, there is grade, and animal guards at the end.....it wont plug. Its burried in the ground so looks dont matter. corrugated is a quarter the cost and works just the same. Tees and fittings are also cheaper and easier to assemble. Everyone suggesting using rigid PVC or something is just suggesting you throw money away. Just my 2 cents

 

[dirttoys]

For what it is worth (free).

I have had as good a luck with black corrugated as I have anything else, it is cheaper and mostly easier to work with (this opinion might be worth a dollar).

There are lots of folks that have done more of this than me, so.........

I hate digging up tile enough, I dump my eaves above grade onto clean gravel that buries the drain tile. I can pick up the pile of crap off the gravel, it never sees the inside of a buried pipe.

Best,

ed

 

[DrewStyduhar]

Hi guys,

Interesting thoughts. I appreciate everyone's feedback.

LD1, regarding your comment below, I imagine the primary issue is cost....no? I don't think corrugated is so much better than PVC where it would still be used if cost was switched between the two?

""There are hundreds of thousands of miles of the stuff in the ground all around me for ag drainage. As is smoothwall old clay.""

Although it definitely has its place, here are some reasons that come to mind about why "I" generally don't like corrugated. I'm sure all these points can be argued but here's my 2cents

1. Roots blow through it. Maybe not an issue in my situation

2. Hate dicking with corrugated in a hand dug trench, it never lays right. I also think its more of a pain to bed corrugated pipe compared to rigid. If its not bed 100% across its length then the low spots in hold water

3. Doesnt flow as well as PVC.

4. My opinion here but I feel that the corrugated ribs hold/snag crap and has more of a tendency to plug up.

5. I'm sure you can manually snake out corrugated but have been told its bad news to use anything with a cutter head

6. Same issue with thinwall where its easy to crush if buried too shallow. Have heard some people say that burying thinwall too deep is bad news with wet/heavy soil also. Who knows. One time I helped dig up that corrugated pipe that was buried fairly deep and found in some places where it was crushed. Might have been a fluke.

7. I don't like how the corrugated fittings join, it feels cheap and temporary. Its like using push fittings in plumbing.....Im a copper guy, haha. I like tight joints!!!

8. I'll be days into digging this ditch and don't want to do it again. If I had a backhoe or something I prob wouldnt be so concerned.

thanks,

Drew

 

[LD1]

1. They make non-perforated so roots are not an issue.

2. I can understand what you are saying. But it's drainage, not precision machining for parts on the space shuttle. Your rigid PVC will flex and have the same high and low spots if the same lack of care is taken bedding. For me, I'd rather not be hassling gluing or fitting a joint every 20'.

3. Incorrect. It flows just as well if not better.

4. Actually the opposite. The ribs actually help keep from building up sediment.

5. Yes, snaking it can be a pain.

6. It wasn't the weight of the dirt that crushes it when buried deep. It's lack of care when backfilling and letting big chunks of sod or rocks land on the pipe.

7. It may feel cheep and temporary....but have you ever tried to get an internal snap coupler out of a corrugated pipe? Trust me....it ain't temporary. And once it's buried, it ain't going anywhere.

8. Either one has the potential to last hundreds of years if done right.

At the end of the day, it's your money and your project. If you wanna use PVC for your own piece of mind, go for it. I'm not trying to convince you one way or the other. I'm just trying to debunk alot of the myths and falsehoods of corrugated drainage that everyone keeps spreading like gospel

 

[EddieWalker]

In the comments, people are talking about cleaning out the pipe that's in the ground. This really isn't an issue. Leaves plug up gutters at the downspout. If you have a decent gutter guard, then leaves are not an option. If you do not have anything to keep leaves out of the gutters, then they all build up in the gutter at the downspout. It's very rare for those leaves to go down the downspout very far. I've never seen or heard of a gutter drain pipe being plugged up from leaves. They just don't get down there that far with enough material to jam up the pipe. It all happens up at the gutters.

 

[DrewStyduhar]

LD1 - The folks here seem reasonable.....If you are trying to dispel some of the falsehoods, why not provide some info to change people's minds? I'm always trying to learn.

Drew

 

[LD1]

LD1 - The folks here seem reasonable.....If you are trying to dispel some of the falsehoods, why not provide some info to change people's minds? I'm always trying to learn.

Drew

.Most of it is just years of experience dealing with drainage. And if someone is more ambitious than myself to google and provide links to flow rates of corrugated vs smooth pipe be my guest. But I dont come here to have my advice and years of experience questioned to the point I need to cite sources to try and prove my point. If you dont believe what I am saying, thats fine. You want to try and find your own sources to disprove what I am saying, be my guest. Im not investing that much leg work in simple free and friendly advice

 

[DrewStyduhar]

Now come on, no need to be like that......I'm not patronizing you. I prefaced my comments about corrugated with "my opinion", I wasn't stating it as fact. You know how it is.....some people will reference text/studies to prove their point but nothing beats experience and real world examples.

I was watching this video last night showing sort of a neat flow test of PVC vs Corrugated. Others might find it interesting?

I'm not real hung up on this whole thing but when you said you were trying to debunk these myths, I thought you were serious. You aren't. It's all good.

Drew

 

[DrewStyduhar]

On a completely separate note, I wanted to let you guys know that if you are stupid liked me and trying to through compacted sandrock by hand, you absolutely need water. I about killed myself and hands digging through it dry. Once I got a shallow trench going, I set a pipe/hose at the top of the trench and let the water run to the other end. I come back every 30 min or so with a hoe and drag out a good inch or two all the way down. The moment water saturates it, the top layer is so easy to remove. Just FYI. Almost to my 1/4"/foot drop, haha.

Drew