Novice installing new bathroom wanting suggestions on waste water pipes

[Pavesa]

Hi

I have a 150 year old house in Nova Scotia that I bought 4 years ago and have been working on - previously pretty much untouched for 40 years! I should add that I'm fairly good at woodwork - helped my Dad with our boat as a kid - and have successfully done quite a lot around here including building a fabulously successful woodshed. I've never touched or even thought about plumbing in my life though, so I'm looking for some guidance.

The house only has a first floor bathroom and I'm in the process of installing one on the second floor in a large closet I've extended to make a compact shower room/toilet. It's going reasonably well so far although plans scarcely resemble original ideas with unforeseen beams and wiring and stuff in unexpected places. Still, I seem to have arrived at a configuration that looks like it is going to work. I bought a Toto Drake C743E#01 toilet with a 12" rough in and a round bowl based on review on your website and elsewhere - seems a great toilet and I've had far far too much to do with blocked toilets in my life! I've taken up the relevant floor boards to gain good access, I've cut the hole for the shower cut a hole for a forced-air vent which will usefully give access under where the sink is to go to enable me to connect everything up there. I have found a route through the bathroom downstairs for the pipes to go (including forced air heating) which is reasonably accessible and gives a pretty direct route down to the sewer pipes downstairs in the basement. So my next job is to connect the waste-water pipes - I think?

As I say, I've never had anything to do with plumbing so I'm wondering if there is a complete beginner's guide to waste-water pipes on the website? I think I have a lot of the basics worked out. 2" pipe from the shower will have a Y connector to a 1.5" pipe which will go to the vent thru the wall (1.5" is acceptable in here in NS when connected to 3" in the attic which goes thru the roof). That 1.5" pipe will in turn have another Y which goes to a 1.5" for the sink drain. All will angle down to enable flow. I have plenty of room so I can be well over minimum angle to give a good flow.

The 2" from the shower will connect to the 3" main sewer out of the bathroom. It's the connection of the toilet that I feel a bit lost. I can see from the outside that the flow of water inside the Toto toilet means that it exits the toilet at about 45 degrees. Given that Toto toilets give a very powerful flush I think I need a flange at 45 degrees as well so as not to disrupt the flow and I should then use gentle curves to connect the toilet to the 3" sewer main below. This keeps the momentum of the flush going without interruption, nothing to snag on to cause a blockage and no build up of deposits that could cause a blockage. I spoke to my local hardware store and the guy was showing me a vertical flange and saying that's fine, but it does seem to me that this would disrupt flow and potentially cause a blockage. Am I on the right lines so far?

I'm rather conscious of the possible need for access to the piping at a later date and the need not to dismantle the entire shower room to do so. So I'm thinking of making sure that part of the floor can be taken up without having to tear out the entire bathroom. I'm thinking of having as many of the pipe connections as possible located under this accessible space. The 1.5" vent to 2" shower connection, the 2" shower to 3" sewer connection and the toilet to the 3" sewer connection as well as many of the hot and cold water pipe connections as possible. I'm also thinking of having the toilet connect to the 3" sewer with a Y so I can blank off the end of the pipe with a screw on cap and get access from the accessible space with an auger in case there's a heavy-duty blockage. In terms of the order of things on the main sewer pipe; from the screw cap downstream, there would first be the cap, then the Y connection from the 2" shower pipe and then the last thing would be the 3" connection from the toilet which would also be a Y connector. The connecting pipe would be angled so that when looking from the bottom of the Y the joining pipe would be (say) at an angle of 5-10 degrees from the horizontal to prevent backflow from the sewer pipe.

The shower will have a P trap. My hardware store suggested a back water valve on the 2" pipe to the shower, but I think they were just trying to make a sale and I understand back water valves are really only needed where there's a slope and a chance of sewage flowing back on the main sewage line from the house. Also, I see it as a mechanical part that at some stage may break down and cause problems. I'm using cell core ABS piping which had a good offer on at my hardware store. I'll make sure the core is sealed with adhesive when I assemble it.

That's my thoughts so far on this. I have looked around on the internet, but I've found rather little on brand-new installations, everything seems to assume all the pipes are already in place. As I mention I'm a complete novice on this so eager to receive suggestions on the many things I'm no doubt unaware of!

Sorry for this very long post and thanks for any thoughts!

Pavesa

[wjcandee]

Terry often cites to this excellent piece: http://www.co.lincoln.or.us/planning...mbingguide.pdf

I found this one a while back, and it covers some different ground and some of the same ground a little differently; I find it helpful to have both: http://www.klickitatcounty.org/build...andout0411.pdf

They should help you get started on putting something together.

[Pavesa]

Hi wjcandee

thanks for the links, looks a very useful set of documents for a beginner..

Pavesa

[wjcandee]

My pleasure! Good luck, and I hope we'll see more from you on here.

[jadnashua]

A licensed plumber is an apprentice, learning how to do thing the right way for years...it's often not as straightforward as some people think. Getting something to work doesn't necessarily mean it would pass code and work in all circumstances caused by changes, or unusual circumstances that may only occur rarely. So, trying to conjure up a full house drainage system may be beyond your capabilities. You might want to seek some professional help, and trying to get it from a DIY'er forum on something of this scale would be tough.

[Pavesa]

Hi Jim

thanks for the advice and I certainly appreciate that plumbing isn't necessarily as straightforward as it might seem, that's why I posted on the forum to get some guidance. An interesting thing about this house is that it was previously owned by the guy who ran the water system where I live.

1) Pipes for the eavestrough were installed upside down so the water ran outside rather than inside the pipe

2) The sewage pipe in the basement was unsupported and was U shaped

3) The sewage pipe out of the wall to the main sewer sloped into the house rather than out

4) The basement was half concreted, but the slope ran away from the sump pump rather than towards it and it flooded whenever there was heavy rain

5) There were no eavestroughs at the front of the house (slope is front to back) so water ran into the basement

6) The downpipe from the eavestrough at the back wasn't far enough from the house so the water ran back into the basement rather than away down the slope from the house

It's a real problem getting stuff done here because of the amount of totally dud workmanship around. Also, unfortunately, unless I do this myself it isn't going to be done.

The documents cited by wjcandee will be really very helpful. I'm kind of really focussed on the kind of flange I should go for. Should it be in line with the outlet from the toilet. Seems so to me.. am I right or wrong?

[jadnashua]

Ideally, a toilet flange is mounted on top of the finished floor, and anchored through it well to the subfloor. You want to avoid having to use an offset flange, so the waste can go straight down, then curve away in the drain pipes. I think this is addressing your question. Sounds like the guy that did the work originally either didn't have a clue, or didn't care which is unfortunate. For the biggest selection of toilets, the center of the flange should be 12" from the finished wall (and in the USA, you need 15" on either side of the toilet's centerline to an obstruction).

A few very basic concepts: a drain can never later become a vent; once a vent, always a vent; once a drain, always a drain; you can't go from a bigger pipe into a smaller one, only the other way; s*** only runs downhill!; all traps need a vent (but you can combine them if you follow the rules). May seem simplistic, but it appears the guy who worked on the house before you didn't know some or all of them!

Good luck...

[Pavesa]

Hi Jim

thanks for the posting and your advice. I had thought of going for an offset flange but with the offset in line with the outlet from the bottom of the toilet so everything would be in line so no lost momentum. Seems like that may not matter. Posting on this site has been really helpful. The other peculiar thing is that there is no external vent at all on the current toilet on the first floor. It seems there's a sort of one-way valve in the basement that's used instead of vents in islands in kitchens and that's what's been installed between the shower & sink traps and the toilet outlet. I should plan to connect that to the vent upstairs and out of the roof.

What's frightening is that the guy who owned this place was in charge of the entire water and sewage system in the village where I live! Goodness knows what's lurking under the sidewalks!

[jadnashua]

An AAV can't be the only vent into the system. An AAV only lets air into the pipes, but there are times when draining something might create a pressure wave, and need to let air out, an AAV won't let air out if it is working properly. Something like the cobbler's own shoes comes to mind...hopefully, the infrastructure is better than what was done in his own place.

[Plumb-Perfect]

Hi Pavesa,
You have been the beneficiary of some really good advice!
If I can add something, my favorite way to lay out the rough in for a 3 piece bathroom where the main run is going to be 3" is to utilize a 3" double wye on the flat; glue in 3"X2" bushings in two of the three arms, one for the shower, one for the sink (which will be called a 'wet vent'; then to use a 4"X3" 90 stubbed up through the floor for the toilet. You are going to completely finish the floor in your bathroom, then cut the 4" ABS off flush; glue in a 'flush fit' 4X3 flange, not adjustable, and at 12" to center off rear finished wall. On the sink run, go from horizontal to vertical with a 'broke back 90' (two 45's separated by at least 2" of pipe); install a 2" 'line clean out about 10" off the floor, then a 2"X1 1/2"X1 1/2" tee picking up the sink. Fool-proof! The only caveat is that you have to be careful not to exceed the acceptable length permitted between the shower p-trap and the double wye, but at 2" diameter you have nearly 8' at 1/4"/ft.

[Pavesa]

Hi Plumb-Perfect

thanks very much for your advice, I really appreciate all the help I have received here plus the documents that have been pointed out to me.

This is going to be a very small bathroom 75" x 81" end even there, about 20% of the area is lost to a chimney. Still, I think it will all fit in fine - shower, sink and toilet.

My plan is a wye 3" with the toilet connect into the straight leg of the wye. Follow the straight let of the wye and it leads to the sink so I have a 45 degrees attached to the angled leg of that wye that leads to a pipe and I'm putting a 3" 2" wye at the end with a cleanout on the straight leg.

I have another 2" wye, leading to the shower and the vent which has the sink attached.

Very interesting idea to use a 4x3 flange with a 4x3 90"

This link gives the idea

http://perso.wanadoo.es/andrew.bagle..._pipe_plan.htm

thanks again for the help and I really appreciate any thoughts. I've not got to glueing yet!

Pavesa

[hj]

quote; I'm rather conscious of the possible need for access to the piping at a later date

WHY?? We install plumbing systems every day and NEVER provide access for "possible future need". It is too laborious to follow your description and decide if you are going to install the piping properly. HOW someone did "plumbing" on the house in the past is a reflection on HIS ability, or lack of it, NOT how someone else would do it or any future work.