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BowhunterNJ

Plumbing SDR35 and Schedule 40 for outdoor drainage

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Let me preface by saying I have no idea what I'm doing.  Pretty sure Todd's cat knows more about plumbing than I do...so this will be fun

I have an existing underground 3" SDR-35 (3.25" OD) waste line for gutter drainage around some of my house that the former owner had installed.  I partially dug it up to figure out what I was working with and verified the OD and thin walling.  I need to extend that to a new gutter location, which I can slope properly to reach the existing line and continue the flow.  I also need to hook in a 1.5" Schedule 40 PVC line from a sump pump in my basement (which will probably never run but was needed for code), as well as another (TBD sized) line from a dehumidifier (which I have yet to get) into that same waste line.

I think I have most of the layout figured out, however I am not sure where I can get the supplies or what I need part wise to go from 1.5" S-40 to 3" SDR-35 .  I'm thinking I can use a sloped T fitting (3" to 3" SDR-35) but need the top of the T to be 1.5" S-40 OR I need to do some kind of adapter from the top of the SDR-35 T to the S-40.  

Can anyone direct me on a part for the above 3" SDR-35 T fitting to 1.5" S-40 , and also where online I can order?  I went to Lowes the other night and they didn't have anything in 3" SDR-35, nevermind adapters/fittings for SDR-35 to S-40.

I have this store/parts counter near me, but I think it's for contractors only?  Either way I'd be going in not knowing anything, but I could try and see what they say, maybe I'll run into someone who wants to help get me on the right track?

http://www.grovesupplyinc.com

 

Edit:  Picture is worth a 1000 words, so that's what I'm trying to do.

You'll see the gutter there, and the SDR-35 waste line against the house.  You'll also see the sprinkler line interfering.  Then you'll see a black rag to the right, that's an existing hole in the foundation where I plan to reuse for the dehumidifier drainage.  Then you'll see on the left of the sprinkler line where that sump pump line is which I think Todd's cat broken trying to adjust it...at least that's the story I'm sticking to.  Anyway, that needs to get fixed/re-run and tapped into that same SDR-35 line.  Ignore the S-40 1.5" to  S-40 3" reducer on the ground and duct tape around the SDR-35, that seriously was not my doing, that's what I'm trying to fix because clearly it was jacked up. 

 

IMG_9219.JPG

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Get a fernc coupling and go from 3" sch 40 to the thin wall sch 10. Then use regular schedule 40 fittings from HD. 

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They do make couplings and bushings to go from sdr 35 to schedule 40 but I have only seen them in 4" The problem is anything under 4" sdr 35 is not commonly used. You best bet is plumbing supply. See if they can get you a 3" sdr 35 wye and a 3" sdr 35 × 3" schedule 40 coupling. Then you can reduce to 1 1/2 from there.

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Something I just thought of. I know this works with 4" so it should work with 3" The hub of sdr 35 fitting is about the same size as schedule 40 pipe. So you should be able to glue the hub of the sdr 35 inside a sch 40 fitting.

 

What your doing is glueing a fitting into another fitting.

Trying to send a pic but it won't upload

 

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OK so I think what you're saying is the bulb end of an SDR-35 waste pipe will fit inside an S-40 OR if they are the same size I could use an S-40 coupling to join them.  Then just run S-40 from there.  I'll see if I can find the OD of the SDR-35 bulb vs the ID and OD of the SD-40.

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OK so I think what you're saying is the bulb end of an SDR-35 waste pipe will fit inside an S-40 OR if they are the same size I could use an S-40 coupling to join them.  Then just run S-40 from there.  I'll see if I can find the OD of the SDR-35 bulb vs the ID and OD of the SD-40.


The hub or bulb lol end of the sdr 35 fitting will fit tight inside a sch 40 fitting. The od of the hub of a sdr 35 fitting is the same od as sch 40 pipe of same size.


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Well here’s how this job went. Came together pretty well for my first time messing with plumbing. Lesson #1 is loosely dry fit. I was being overly critical measuring and put a few pieces together a little too tight/much and proceeded to literally break them in a vice trying to get them apart. Tossed those, fortunately I had spares. Moving forward I’ll just follow the measure thrice and cut once process. Then I had fun with primer and cement! That stuff is a mess! I learned here in N.J. you can’t use the all in one primer+cement mix per the plumbing supply house’s employee who is a master plumber. Measurements were pretty good until the last piece where I went from 3/4” to a 1-1/2” T. Was off a little but had enough flex to get it set. Should be ok.

 

 

I started by cutting a section of that existing waste line back and ran a hose for 15 min or so to make sure it drained well. I don’t know where the termination is, I’m assuming a gravel pit. It’s 150+ feet of sand here so drainage is fine.

 

Tied in the gutter downspout the same way others were done. I have gutter guards now so no debris should ever reach the waste line. If I didn’t have them I’d probably put a leaf/debris guard. I also would have a cleanout somewhere in case it were needed. Will see how things go.

 

Also tied in a sumpump from the basement correctly now with the right sized fittings. Part of the reason I cut back the waste line was to remove a section that was filled with sand due to the previous misfittings. It also gave me more room to work with.

 

Next I reused a 3/4” hole in the foundation which was previously used for my attic air handler condensate drain line. Post renovation it exists elsewhere so now I ran 3/4” that terminates inside the basement for a dehumidifier drain line. I’ll get one that can pump up and out versus manually emptying it in the summer like I do now. Automation!

 

I foam sealed the entry points as best I could. Will review and silicone if needed.

I’ll paint the pvc as well to protect from uv breakdown.

 

Ok I think that about covers it!

 

Here’s the sequence...

 

Before

IMG_9219.thumb.JPG.b5509cb6fde5cd355a1ac4ce868b59c7.JPG

 

Rough layout and pitch

IMG_9273.thumb.JPG.45eb6e7a1341205f414f67641b33da1f.JPG

 

All together primed and cemented

IMG_9278.thumb.JPG.e56543c10ecd85195a35a7af03a2de5b.JPG

 

And hauled several carts of sand from my woods to fill in the area

IMG_9283.thumb.JPG.700619ed11c6ef1fb1e56dcf466a6aba.JPG

 

 

I think the hauling carts of sand was the most work. Another reason I need a tractor!

 

 

 

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Sorry I didn't see this till now -- I'm going to give you something to think about

1st off, I'm an irrigation installer for over 30 years -- Only use PVC pipe --  have built countless drainage systems as well -- I've made tens of thousands of PVC pipe connections -- rarely use primer on anything thats not under pressure and outdoors -- PVC connections that are properly seated all the way into the fitting, are free from dirt,  and have enough glue on them do not come apart easily -- using primer didn't hurt -- just not as necessary as the master plumber made you think it was 

Some thoughts --  3" is too small -- How much roof are we talking? -- how many leaders are tied in to any 1 piece of 3"?

Here's where I have issues with what I see -- the sump line and dehumidifier shouldn't be tied in with water tight connections -- You don't know where this line terminates or empties

What if it's some sort of dry well -- what if the dry well gets full? -- where will the overflow of water go from your roof?  How about potentially pressurized water being pumped from the sump?

Lets just say that the dry well is full, or the pipe is clogged and cannot empty -- the water will find the next lowest exit, from what I see in the picture it's the dehumidifier line -- Your roof may potentially drain into the dehumidifier -- Your sump pump may potentially pressurize the line and drain into your dehumidifier -- It's hard to tell in the picture but you also run the risk of rainwater from your roof emptying into your sump pump

 

I will never run a sump pump drain into a sealed pipe unless it's dedicated to the sump only -- If I'm tying into a combination sump/roof drain I'll make the fitting to tie them together 

I make the fitting using a sdr 35 cap, in my case never smaller than 4", then drill a 2" hole in the cap with a hole saw -- now slip the sump line down into the drilled hole in the cap leaving it loose to breathe and flex --drop the sump pipe down into the other, drain pipe 12" or so --  Depending on how new the construction is the dirt around your foundation will settle -- the loose fitting gives the pipe some room to move and not break

 

At this point your build you should work in some sort of overflow into your system -- give the water a safe place to drain above ground if the unexpected happens 

 

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Sorry I didn't see this till now -- I'm going to give you something to think about

1st off, I'm an irrigation installer for over 30 years -- Only use PVC pipe --  have built countless drainage systems as well -- I've made tens of thousands of PVC pipe connections -- rarely use primer on anything thats not under pressure and outdoors -- PVC connections that are properly seated all the way into the fitting, are free from dirt,  and have enough glue on them do not come apart easily -- using primer didn't hurt -- just not as necessary as the master plumber made you think it was 

Some thoughts --  3" is too small -- How much roof are we talking? -- how many leaders are tied in to any 1 piece of 3"?

Here's where I have issues with what I see -- the sump line and dehumidifier shouldn't be tied in with water tight connections -- You don't know where this line terminates or empties

What if it's some sort of dry well -- what if the dry well gets full? -- where will the overflow of water go from your roof?  How about potentially pressurized water being pumped from the sump?

Lets just say that the dry well is full, or the pipe is clogged and cannot empty -- the water will find the next lowest exit, from what I see in the picture it's the dehumidifier line -- Your roof may potentially drain into the dehumidifier -- Your sump pump may potentially pressurize the line and drain into your dehumidifier -- It's hard to tell in the picture but you also run the risk of rainwater from your roof emptying into your sump pump

 

I will never run a sump pump drain into a sealed pipe unless it's dedicated to the sump only -- If I'm tying into a combination sump/roof drain I'll make the fitting to tie them together 

I make the fitting using a sdr 35 cap, in my case never smaller than 4", then drill a 2" hole in the cap with a hole saw -- now slip the sump line down into the drilled hole in the cap leaving it loose to breathe and flex --drop the sump pipe down into the other, drain pipe 12" or so --  Depending on how new the construction is the dirt around your foundation will settle -- the loose fitting gives the pipe some room to move and not break

 

At this point your build you should work in some sort of overflow into your system -- give the water a safe place to drain above ground if the unexpected happens 

 

 

 

Great insight and info! This 3” waste line does join with another downspout further down the roofline, so that would be the next lowest I believe and should flow out of it during a backflow since it isn’t a sealed downspout connection. I do have a back flow preventer on the sumpump but it’s obviously a single point of failure. Good point with the dehumidifier. I actually asked about running that into the waste line vs elsewhere and he suggested just tapping into it. Now that seems like a risky move.

 

FWIW I’ve never actually seen water in my sump pump well. My basement gets very humid in the summers but is bone dry in the winters. As mentioned earlier it is all sand here which probably helps a lot with drainage but isn’t a guarantee. Also the house is around 30 years old so this was all renovation work. The previous gutters would overflow a lot on heavy rains. Maybe poorly pitched or installed, I cleaned them of all debris and the old downspouts exited to open ground level diverters or into a waste line with an open downspout connector. The new gutters are wider and should help route the water better/faster.

 

Also not that it really means anything but the previous owner owned a landscaping business and installed the original drainage. I hope he did it well but I honestly don’t know. I’ll see how things go and will keep a close eye on it. Thus far, knock on wood, I have yet to see any semblance of flooding or water retention with the exception of frozen ground and melted snow and rain pooling for a short period. In non frozen conditions I’ve never seen water pool at all anywhere. I’ve also never seen the underground waste lines backflow to where the downspouts enter them. However all it will take is one minor backflow into the basement and I’ll be seeking out a better install for the system. As a fail safe I could put a backflow preventer on my dehumidifier line to protect it. Might be a good idea just to do that for now.

 

 

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You could just add a tee outside, where the line goes down into the main drain line -- leave the one side of the tee open to air as an emergency drain, maybe put some screen or mesh over the open portion of the tee to keep the critters out -- Lots of times a system will require open tees at each leader as overflows -- we'll put a slotted drain fitting type plug held in with a stainless screw so it can be removed for cleanout -- remember this is 4" though -- you'll have to get creative with that small dehumidifier line

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Yeah was thinking about that last night. Lower down the line I could put a T in with a grate as an emergency overflow. It’ll be a royal pain because once the waste line exits the last downspout it’s already like 2.5 feet down. He had it on quite a slope. From what I read it should be minimally 1/2” per 10’. He was like 1/2’ per 10’. I’ll have to trench it from there out into the yard to get that overflow away from the house.


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Took a couple pics today of the heights relative to the house. Siding is level so measurements should be accurate.

This is at the intended dehumidifier location, the lowest point of the three inputs I put in yesterday.

IMG_9292.JPG


This is the height of the other downspout that is tied in at the end of the house. Since it’s lower and open, water should flow out in an overflow situation. That’s good as it shouldn’t allow backflow all the way up to the dehumidifier or sumpump. However if it happens I’ll need to dig out the bottom of the line and figure out why. That’s the area I’ll keep my eye on.

IMG_9290.JPG

IMG_9289.JPG


Anything else I should be concerned about or keep an eye on?

Thanks for the insights overall. Much of it makes perfect sense! :up:


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That should be fine. But like heavyopp said an overflow tee at the downspout termination would be better. Also the humidifier pump has a check valve on it and so should the sump pump. So that would prevent backflow into those two pumps.

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Ok looking at this last picture,  If thats the lowest part put the overflow tee there 

Pull off the pipe to leader adapter, install tee with output just above ground and put some sort of grate in it, cut aluminum leader a little shorter and get it in the top of the tee

Do that and I would think you'll be pretty safe from an overflow ending up inside the house

If that leader adapter is glued on, you can still get it off but you will have to sacrifice it -- you can save the pipe most of the time -- using a hacksaw blade cut vertically down the fitting splitting the fitting -- you can try with a utility knife too but it will take longer -- just be careful not to cut the pipe -- once you have the fitting cut use a screwdriver in the saw kerf to open up the fitting -- should pop right off -- sometimes you may have to chisel a stubborn fitting off -- also that thin walled white SDR35 pipe might make it harder to separate the fitting from the pipe -- it's still worth a shot, will save time, digging and a fitting or 2 if it works

The pitch that you read about is mainly for sanitary sewer pipe -- you don't want the pitch too great because the solids will separate from the liquids potentially causing the solids to stop moving down the pipe -- you shouldn't have that issue in your rainwater drain system so the excess pitch if of no concern 

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Well it didn’t take long to test the system.  Glad I was home because not only did it flood out the low point but it backed up all the way to the other points too.  Had some minor flooding into the basement that I caught quickly enough.  Looks like I’ll be recruiting a drainage installer to get this and a couple other areas right.  What area you work in Heavyopp? :)

Videos from tonight...not good!  That waste line obviously isn’t terminated properly.  

Low point then higher point.  All that water no good around foundation, definitely have to get it fixed right.  

 

 

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At least you where aware of a possible issue and paid attention to it 

I'm in Middlesex Borough -- Zip is 08846 

What town are you in? 

It still may be worthwhile for you to explore where that pipe terminates even though it is only 3 inch -- depends on how big your roof is and how many leaders are piped into the 3 inch 

Honestly, my feeling is 3 inch is just too small for anything more than 1 leader -- think about the internal size of a 2x3 leader compared to the internal size of the 3 inch -- Not much difference...

 

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Oh ok, I'm down in Southampton 08088.

There's two downspouts into it, although I do think you're probably right that any more than 1 is too much for it to handle.  I'm going to get some estimates on that and some other drainage/plumbing work and go from there.  If you're interested, definitely shoot me a PM and we'll work out a time to go over it here at the house.  If it's too far, that's OK too.  :up:

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Yea unfortunately thats longer than I want to drive in the trucks 

Keep the pictures coming and I'll supervise from here

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I just had this job done by a landscaper yesterday.  He used 4" pipe and said it should take anything. Mine goes to the street so it's a little different.  He also put in a cleanout just in case.

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Generally when I want them to take "anything" I'll use 6" sdr 35 --I've even used 8" on commercial projects

It's all relative to the size of the roof and number of leaders

 

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So I did make a few calls yesterday to get some appointments for estimates.  I spoke with one of the higher rated (Google Reviews) landscaping companies and he explained that he only uses hard (assuming SDR) waste piping, nothing corrugated (I agree per what I've read).  His approach is to run all downspouts a minimum of 20 ft away from the house with 4" and then he terminates that 4" waste pipe into a 5 gallon bucket filled with stone and has holes drilled in the bottom of it.  From there he T's upward to a 9" catch basin at ground level (for overflow?).  This sounds like a decent plan to get water away from the house, however I'd imagine that bucket will probably fill pretty quickly anyway and water will flow out of the 9" catch basin.  I guess that's the unclear part.  I've seen videos where some people just use a pole hole digger to dig about a 5' hole where the 4" waste line terminates and fill it with peastone up to a T at the waste line termination then run the top of the T to ground level with a grate top for overflow and to use as a cleanout.  Both are similar ways, just one is a post hole vs a 5 gallon bucket.  Either way, I don't think either will be able to handle more than one downspout without overflowing pretty heavily.  Maybe the overflow is just fine given it's away from the house and especially where I'm at, is all sand and does drain pretty quickly...the exception being massive downpours (which is also where I had my problems described above).

 

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