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SOIL PIPE INSTALL – HOW TO CALCULATE FALL GRADIENT

SOIL PIPE INSTALL – HOW TO CALCULATE FALL GRADIENT


– Hey guys, welcome to today’s
Plumberparts.co.uk video from the studio. Like pretty much the first
video I think I’ve ever done from this little studio. As you can see, we’re right in the middle of building everything up at the moment. Got the heatin’ goin’, we’ve got our soundstage set up and our little stage area
that we can move ’round, make into different rooms
and things like that. Super excited. Can even fit the beast in there. Let’s have fun. We’re gonna be looking at soil pipe today ’cause that’s what I’m fittin’ here. Thought it’d be a great
opportunity to tell you a little bit about falls
and bits and bobs like that. Please follow us on Instagram, Facebook, Snapchat, and Twitter,
and subscribe as well. See ya in the video. Hold tight. (upbeat music) So in here just behind
us we’ve got (mumbles) So we’ve got 4 inch comin’ out of there. Just over there we’ve got a kitchen sink and also a little sort of kitchenette bit, and then also a little basin as well so you can wash your hands
after you’ve done a wee wee or a poo poo ah. And what that’s gonna do
is we’re gonna run that all the way through down here and just outta shot down there
by about another 3 metres. We’ve got our main drop pipe going in. So what we’re gonna be looking at and where we’re gonna be
workin’ at most in this video is gonna be just along here, around there, that’s oh, oh it’s gonna be great. Thing is, right? There’s a lotta chit chat about drops, bits and bobs like that. Often the drop, you might be havin’ to figure it out or work it out or anything because you haven’t really
got much of a choice, and let’s talk about why now. So often the fall for a
waste pipe or a soil pipe isn’t really gonna be anything you can define yourself properly. If we get out this lovely bit of 9 mm MDF, I think it’s 9 mil, I don’t know. Let’s have a quick look
at what most jobs are. So most jobs you’re gonna have a house like this. Okay? And you’re gonna have two floors. There’s gonna be a waste pipe
that sticks out like that, and maybe the dropdown stack is here. You’ve already got a T-bar in there, and you are just gonna
be running that down into your old branch. When you’re doing new jobs, okay, a lot of the time we sort of work between two areas of drop and fall. I mean you may have heard someone say, It needs a drop of 1 and 40, or it needs a drop of 1 in 110. And that’s like the lowest, so 1 in 40 is really quite steep, and 1 in 10 is much more shallow, and that’s kinda the spectrum. If you’re anywhere between there your drop is gonna be
probably just about right. But let’s figure out
what that actually means. 1 in 40, so for every 40
cm across you’re going, you want to drop by 1 cm, easy. And for every 110 cm you go across you wanna drop by 1 cm. Now often what you’ll be doin’, if you’re workin’ out falls and drops, is often like soil drainage. It’ll be in the ground, and it’s not something that you’re gonna have to do along the wall, because that’s often predefined. So what I’m tryin’ to say is, for ground workers they are
predetermining their own drops because they’re diggin’ the trench, and sometimes they’ll need
like little break tanks and things like that if they’re goin’ down a hill to make sure that they
haven’t got too much or too little drop. That’s fine. But for what we’re looking at, which is often grey soil pipe that you’re gonna be
putting up outside a wall or somethin’ like that, you’re often already predefined by the branch that’s there already or the toilet hole that’s
comin’ out of the wall. You can’t be changing the
toilet height much can you? Let’s face it. I mean there are things
you can do behind a toilet like elbow it down, so you know you’re outlet
hole is a different height, that sort of thing, but most of the time we’re going to be going straight out the back. (upbeat music) So the job that we’re doing today, as you saw, we’re gonna be
coming out the back of the toilet with a standard toilet pan connector, like a McAlpine Multikwik, then we’re gonna be going
into a 4-inch elbow, and then we’re gonna
have two lengths of pipe. So that means we’ve got a 6 metre run. Now that’s important because the first thing we’ve done there is we now know one of the dimensions that we need to figure out to
know what our gradient is and also whether it’s okay. So if we go on the rule of thumb that the shallowest possible drop that you’re allowed and is permissible is for every 110, all right, to make it
easier I do for every metre you want a minimum drop
of a centimetre, okay? So we’re gonna want a
drop from our outlet here, and what we do for drops is we don’t measure from
the centre of the pipe, we actually measure from
the bottom of the pipe. That’s what I usually do. Everyone’s got their own way of doin’ it. So we’ve got a little
bit of bottom pipe here, we’re gonna want a difference between the bottom of this pipe here and when it goes into our T-branch, we’re gonna want a difference of roughly 6 cm across this whole lot here. That is a rule of thumb. It’s not something you
have to stick by 100%. To be honest, I’d much prefer to be able to maybe be able to do it so we’ve got 1.5 cm for every 1 metre that we’re going in
our travel across here. Those parameters there are
just there for guidance. So what we’re gonna do is
we’re gonna stick our pipe in. Matt the plasterer was
’round here earlier on, so I gotta kinda be careful with the inside bit of the toilet ’cause there’s quite a
lot of wet muck up there and he’s gonna get the goddamn up if I mess up his plaster. One thing I wanna say as well guys, please follow us on Instagram because this week has been an
interesting one on Instagram. – We’ve got a master of
his trade here today, Matt’s here. Look (mumbles) Studio’s comin’ along pretty well. Ted, Ted. What’s this? What’s this? This is my pencil mate. No, no it’s not yours. It’s mine. Git. Things like that, if you’re interested. Follow us over on Instagram. I’ll leave a link that
should be appearing right now for you to go and click on there, and also there’s a link below as well. So anyway, let’s go over
and actually have a look at where we’re gonna be doing this and how I’m gonna get this job done. Another funny thing is about
having a little doggy onsite, I was bending over doing
some prep work for this, which is why there’s a
little puddle over there out of shot, but we’ll see that in a minute, was Ted started lovingly
nuzzling my bum crack, which I thought was really quite funny, and also strangely arousing. Why have I drilled a hole here? Let’s firstly just cover that quickly. Well, it’s quite simple. I know that my toilet is gonna
be sat on this floor here, therefore, I knew exactly where my height of my toilet outlet was just by measuring up from where it sat on the floor to halfway
up the toilet outlet, and then I knew exactly
where the centre was to drill my hole. How did I know how far to
drill out my hole on here? Well obviously it’s very important, and I try to run on the theme that for every 3 m length of pipe
you want at least two clips, and that’s why our clip (mumbles)
is gonna hold our pipe out so it’s this far off the wall. Very easy for us to figure out. We just pop our clip on the wall here, and as you can see, that’s bang on right for
getting that in there. Very quick tip about clips. A lot of people make this mistake. There are two type of clip, and don’t get this the wrong way ’round, ’cause if you do you’re
gonna go absolutely mental. One is for the actual pipe run, but one also will take
the width of a socket, so it’s bigger, all right? And that means that the
pipe’s gonna sort of rattle about on it. It’s very rare that you
really want a clip socket. You’re more likely to be getting clips that’s gonna actually fit the pipe itself. So I gonna have it up here like that. If I can, I’m gonna sort of put
my finger under here. So the bottom of our pipe is about 14 cm. And now, really important for us to do, is to pop over right over to here and see what we’ve actually gotta go into. Let’s have a look at that now. So we are gonna be going all the way down to the darkest depth. We’re gonna put a T-branch in here because I’m gonna be wanting to maybe put a toilet in there to film it, and I wanna show you guys exactly how all the waste pipe works for that. I’m just thinkin’ of you. Remember that, all I’m thinkin’ of is you. So we’re gonna be running
all the way down to here, and as you can see we’re
just gettin’ into a wet bit because I got my plasterer to pour his water down there earlier. So look, I think we can see already that if we were gonna measure from the bottom of the
pipe where it goes in here, this is our kind of no
way back sort of area, we’re gonna measure from there down. That’s gonna be about 10 mil, okay? So we know that that’s our depth there. So guys, are we within our parameters? We’ve got a hole going of 6000 mm at one end we’ve got 140 mm, and at the bottom end we’ve got 10 mm, so the difference between
the bottom of the top end and the bottom of the bottom end is, guess what, 130 mm. So firstly, let’s figure
out the maximum amount of steepness we’re allowed going along with the rule of 1 in 40. The best way to do this
is to divide our going, so that’s 6000 by 40. That leaves us with 150. Equate that to either 150 mm or 15 cm, and that’s the maximum amount of drop we’re allowed between the top and the bottom of this run, and as you can see at the moment, we’re well within that tolerance. So let’s have a quick look and see the minimum amount of fall we’re allowed. So we get our 6000 and divide that by 110. That comes out at 54.54, which is 54 mm. So to be safe the minimum amount of drop you want along the whole
of the going of this is gonna be 6 cm, really. Now I know that I’m well
within the parameters that I’ve set myself for this job. I’m happy to carry on and start installing the soil pipe on the wall. Just a couple of little (mumbles) tips, if you’re onsite as well, if you wanna do any cutting, I always go out to the chippy, see if you can get any V pieces, and you can just sit that in there. And you wouldn’t believe, actually, how well that holds here
for you to cut the pipe, ’cause this can be a bit annoying to cut and roll about quite a bit. Also you are going to
want, whatever cut you do, to get a rasp or get a file or if you’re really lucky
you can actually get a proper deburring machine, to
put a chamfer on this, because you are pushing it into a fitting that is exactly the right size. And also, you’ve got a really thick kinda rubber insert there that
makes up our watertight seal. Along with that as well, you’re gonna want to get some
sort of lubricant for this. You can get a silicon spray lubricant, you can use Fairy Liquid, you could even spit on it and
just rub that ’round there as if you’re on porn set, and then that’ll get
it going really easily. I’m gonna do the old porn set one ’cause I don’t know
where any of my stuff is. I’m building this. I’ve got like two jobs on elsewhere. I’ve got work on at the house, and I’ve got tools all over
the country at the moment. It’s drivin’ me nuts. Now what we’re gonna do
now is we wanna make sure that our fall is nice and straight, that these two are nice and perpendicular. We’re gonna put a cap in this, so we don’t have to worry about that later and up that and I’m gonna
put like a metre stub on and a durgo as well. A durgo is an air admittance valve. But anyway, the reason we’re not putting these together
just yet is obviously we want to get our clips hung. We wanna make sure that
everything’s perpendicular and straight all the way down as well. A good way that I like to do this is to think about my centre clip first, and divide everything from that in half. So we know that we’ve
got a run of 6 metres, so if I measure 3 metres down
we’re roughly gonna be here. We know we’ve got our 14
cm there and 1 cm there. So we’ve got a difference of 13 cm. We divide that by 2, that’s 6.5. So we know then that
roughly here our clip, the bottom of the trough, our clip, wants to be 6.5 mm off the ground. And obviously all that comes into bearing as to whether our floor is level and our wall is nice and
level and things like that. So think about that. Similarly what I’m then gonna do is, I know now that the bottom
of the trough clip is here, is 6.5 going up to 14 I can then measure up here, make that difference there as well. But a lot of guys aren’t gonna do that because there’s not
much flex in this pipe, and once you’ve got your one clip here, you can almost just pop the clip on there, mark the holes, and then
whip everything outta the way and drill your holes and get it plugged and clipped like that. (upbeat music) (drilling) So we’ve got a good fixin’ on here now, we’ve got a nice washer, good screw, and that’s not going anywhere at all. (upbeat music) Right then guys, we’ve got it all in. We’ve got our pipe running down here. We’ve got a little
T-branch just coming up, ready for some work that
we’re gonna be doing on the other side of the studio, if you wanna just have a
quick look at that as well. Where that is. Let’s see, that’s the state
of the studio at the moment. But as you can see,
we’ve got a really good adequate drop in that all the way. Nice little gradient on that. And there we’re going ’round
to our T-branch just down here, and I’ve got my durgo and
my little stub ready to go. We did have to go over to putting
our last clip on the floor because the first fixed
pipe work that had been done by the ground workers like months ago was a little bit too far out of the wall for our clips to actually reach. I could have got ’round that another way by like cutting small stubs of copper to sort of stick out the clip a bit more or maybe mounting it on a
little bit of batten wood. There’s loads of ways around it guys, work whatever is best for you. There’s no hard and fast
rule to any of this, that’s the thing. The good thing is, right, we haven’t put our cap I here yet, and obviously if we go down to here, I haven’t put my cap here yet either. So what I’m gonna do, I don’t know if this is
gonna work very well, ’cause I’m on my own today, I’m gonna pour some
water out of the kettle down the 4-inch stub pipe that we’ve got. Let’s see if we can chase it. Gotta be quick. So 4-inch stub pipe’s just here, kettle’s just here, be real quick here, right? There’s water goin’ in there now. Uh. Should better go if we’re
gonna see water runnin’ down. There ya go, water. Then we should be able to go to here. There ya go. You can just see a little
bead of water just there. There ya go, a little
bit of water, hey hey. So that tells me that our
pipe drop is absolutely fine. We’ve got no problems there at all. We’ve got it nice and sturdily fixed. There’s no problems there. And we now know that
whatever we put down there, and believe me on a
Friday I’ve got a little, well I’ll show you quickly. Hey hey, I’ve got a little fridge area that I’m building up as well. This is all sort of outside
of normal work hours. So yeah I’m gonna have
a few beers in there, and obviously on a Friday
crack open a couple of beers, maybe if we’re gonna do a
late night Friday filming, get a curry pot down here or maybe get a Chinese
takeaway dropped off. And then that soil pipe’s
gonna have to deal with it. It’s gonna have to deal with all of it. Yeah. So there we go guys. All done. We’ve got a waste pipe here, and we tested it. We’ve got no leaks. We know our drop’s okay. We know we perfectly fixed it across here, but we’ve also recognised about the fact that there’s no real hard and
fast rules to how to do this. You’ve quite a lot of scope
for how much drop you want, and also when it comes to fixing stuff there’s so many ways of doing it. Obviously make sure that
whatever you’re fixin’ you’re using the right equipment
to do it in the right way. I’ve probably missed
something out in this video because there are so many
different things to do. I will show you that we’re
gonna be bossing into this pipe, so I’m gonna show you
how to do some bossing. I’m also gonna show you exactly how we’re gonna run a cold feed across here, so we’ll be clippin’ it up
and doing that soon as well. So we got lots to do in
the couple of weeks ahead, oh yes. I’d like to remind you, number one, follow us on Instagram. I love Instagram, it’s the best. Everybody loves it. Number two, follow us on Twitter, follow us on Facebook, and follow us on Snapchat. Snapchat’s especially
good around the weekend when I get quite drunk and
I wake up on Sunday morning I’ve got the Snapchat open, I’m like oh my god. Also follow us over on
my other vlog channel, TimesWithJames, I’ll leave a link to that, and also, of course, subscribe. If you need any more help, comment in the comment section below, and I’ll see you soon. Hold tight everybody. Bye bye. (upbeat music) (funky music) Matt I’d like to pay
and I wanna owe you one. – Owe me one? – [James] You’ll ring me up at shit times and ask me to do shit jobs. – I’ve wanted, I’ve wanted
something like this for ages. (laughing) – Evil. If you’ve enjoyed today’s
plumberparts.co.uk video, then please press the
subscribe button now, and before I go let me
tell you a little joke, a funny one, why are giraffe’s necks so long? Well, it’s because their heads are so far away from their bodies. Yep, see you in the next video.

Comments (53)

  1. Making good progress!

  2. bro i wanna work for you

  3. We did this in college yesterday, same working out for gutters too

  4. Why not work back from the lowest point, set your pipe up so that it is LEVEL then raise the toilet end up by 1cm per 1 Meter, if you measure of the floor you could be way out

  5. So the drop should be around 1.0 – 2.5 % or 0.52 – 1.43 degrees ? xP

  6. Studio looking brilliant bud great work, another brilliant video for all the apprentices out there will definitely be sending a link to mine as he struggles with soil. And If Anyone in the comments don’t follow plumber parts on instagram get over there! Lots going on and some great people on the page too that youll speak to along the way

  7. I feel that you need to be admonished for your lavatorial humour, references to bestial acts and pornography. She (who must be obeyed) scolded me for teaching our 4 yr old the pull my finger-blow a raspberry joke. Big mother is watching you!

  8. Good vid.. great new studio!

  9. Forgot to put your cards at the end mate!

  10. Love this channel, helped me loads over many years now. Keep up the great work mate 👍🏻

  11. Studio is looking great! Nice work

  12. 6.52 Micky Flanagan lol studio looks well good btw.

  13. Tim Allen ( home improvements )

  14. You should have floated an onion bhaji down that pipe!

  15. Don't forget to provide George with a nice sleeping station ! Good example of the maths involved to get pipe slope right.

  16. CHECK MY INSTAGRAM INNIT! http://www.plumberparts.co.uk/social.php?social=Instagram

  17. Great video as always.
    Small point though, should your 3m measurement not be 7.5cm of the floor? 6.5cm + 1cm for your finishing height.
    Not going to matter too much as you have a reasonable run on the pipe.

  18. have you ever considered seeing a psychiatrist?

  19. For a waste pipe or soil pipe it’s 18mm per metre so if it’s 3mx18=54 simple

  20. Normally just do it by eye tbh 😂😂

  21. Hi. Just wanna say. Really good mate thanks. Do you know a joiner who is as good as you are at plumbing on you tube. Really good thanks

  22. Is there a video where you show a fix on an installed pipe? Like if there is a belly or a cracked section and you have to cut and replace a section of the pipe. I have an underground portion of my sewer pipe that needs replacing. The pipe is fixed. To get it to move a little bit after I cut it I would need to dig a very large trench which I cannot do. Thanks

  23. I believe when Joseph Bazelgette designed the London sewers in the 1860s, he had a minimum fall of 1 in 200.
    Drainage has to achieve a self cleansing velocity. Too steep, water flows too fast and leaves the 'solids' behind. Too shallow, and the velocity isn't great enough to keep the solids moving.
    Or, just do what groundworkers do when laying drains and they're not using a laser. Just tape a thin piece of wood to one end of your spirit level.

  24. HI James, great channel. Loads of hints and tips. I’m no plumber or apprentice, just an average bloke wanting to give it a go. I looked else where that mentions “breathing?”. I guess if water and soil moves in one direction air moves in the opposite???? Kinda like a bottle of ketchup, I suppose🤷🏻‍♂️? I just read what I wrote and makes no sense!

    Thanks

    David

  25. Ok I got it now, air admittance valve regulations! How and when do I know when to use one?

  26. Bit disappointing you cut the bit when you were spitting on the pipe to lube it.

  27. 18mm per metre minimum gradient please

  28. what a charming helpful man!

  29. Why did you not just pull a string line from the top of the first clip to the top of the last clip???

  30. Get outside in the rain dick

  31. Hi can u tell me if it is safe to bury copper pipes into concrete wall etc thanks

  32. This video could of gone for 3 mins

  33. what is the name of the song

  34. Hey bruvaaa. But what happens if your moving the toilet upstairs? Where there isnt a waste pipe on the outside of the building? (old victorian house with bathroom downstairs through the kitchen style)

  35. I need help deciphering what you are saying but I am keeping up as best I can.

  36. Absolutely mad but very good!

  37. loving the fake grass for a chipping mat 😂 and the wedge above it .. niice

  38. Is it 1/110 because of the size of the watse ?

  39. Should there be a vent somewhere, what is the rule for vent distance way from the pans ?

  40. In nz we do 100mm at 1.65% then 32 to 65mm at 2.5%

  41. Informative and I would have probably come back for more tutorials, but you are stretching it way too long, which was at times way too embarrassing for me to watch your posing.

  42. Does a bend in the pipe around a corner impact the fall gradient? Does it still just need to be 1/40 a 1/110?

  43. STILL UPLOADING TODAY
    PLUMBERPARTS AMAZON TOOL SHOP https://www.amazon.co.uk/shop/plumberparts
    Follow my Vlog, TimesWithJames http://www.youtube.com/c/timeswithjames

  44. so 1 cm per metre drop

  45. if 2 houses are built on a 1 acre land the back house how far can toilet waste pipe run before it needs a pump to push it ?

  46. With all the effort this guy says he's putting into making these videos; you would think he would bother to learn English.

  47. Your plumber card has been revoked for using that centimeters crap. Real plumbers only use millimetres.

  48. 2:08 – I think it’s the other way round. 1:10 is really steep (10% gradient) and 1:40 is quite shallow (2.5%)

  49. Great video again mate really helpful atb👍

  50. This guy sucks, can’t speak English

  51. You are brilliant

  52. Excellent videos, really helpful for us novice DIY plumbers. Keep up the great info!

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