What is the maximum distance and angle permitted for bathroom drainage connecting to the main pipe?

Question

We plan to move the bathroom 13 ft from the canalisation pipe. The ceiling is 3 metres high, so we can raise the floor in the bathroom if needs be to achieve the angel. We are in a block of flats and will need building freeholder and council approval.

We want to avoid a saniflow if possible, but we've been told the distance might be too long. Is that true?

Answer 1

In single stack drainage the lavatory branch can be up to 20 ft. Aim to have the fall 1 in 40 for 4 inch pipe, so you are probably only looking at a rise of 4 inches over the present lavatory height. There may be some problem with the other fittings unless you use air admittacne valves (subject to code).



As you are needing to get approvals - you will need an engineer or a plumber to do a sketch for you.

Answer 2

If you raise the floor in the bathrrom you will now have a step to consider when entering the room, I moved our bathroom location from one side of the house to the other, but I took the waste out through the wall and linked up with main sewer.

I think you should get at least some information from the council as to the requirements for run and fall.

I have noticed that many of your answers have come from people in the US The USA is completely different to our building codes and you should take that into consideration.



Here we have a one quarter inch fall per linear foot , and they have all kinds of things that would never pass a building inspection back in England.



My guess is, that if you live in a purpose built block of flats, the floors are solid concrete, that on it's own would be a challenge. If you do have floor joists, I do not think you would have sufficient space under them to get the desired fall over a 13 foot run. A project like this one is very difficult to judge without actually seeing the lay out of the property, and being able to determine the best route to take.



Just to give you an example of the difference between here and England, they still run a single wire from socket to socket and have never heard of a ring main. LOL When you plug in a vacuum the lights flicker, I am not lying, but all this is acceptable by local code and building permits.



Although I love living and working in the US, it's like stepping back in time within the building industry.





Good luck with the project.





Paul M

Answer 3

If you mean you intend to move the bathroom drainage 13 ft. from the main sewer pipe, then you will need to dig down and run a bathroom waste pipe for the toilet underground. You have to use underground pipe for this and construct a manhole for rodding purposes where you connect into the main sewer. As for a saniflow, you can get literature from a plumbers merchant which will tell you maximum distances, but a saniflow outlet pipe must have a straight a line of exit as possible

Answer 4

You should have at least 1/4" inch drop for every foot of pipe run. You would be looking at 3 1/4" drop over that 13' but I would go with a 4" drop.



We have a 45' run in the basement and it has a 11" drop.

Answer 5

Every once in a while, I just have to get facetious, especially on questions from the UK, which has terminology and construction that is quite foreign to me.

I would not raise the entire floor in the bathroom. I would build a platform just for the "loo" (is that the correct word for toilet?), thus raising it enough to get the angle you need for drainage. I would stair step with one step up to the platform.



This is from experience with a shower we built into a very small bathroom with extreme restricted access to the interstitial space where the drain would go. We platformed the toilet on one level, and the shower one more level up. Each level was a total of just less than 12", as we used 1X10's for the "risers" (for those in the UK, a US 1X10 is about 3/4"X9 1/4" (don't ask me to convert that to cm's, please). Adding the platform was another 3/4" plus a layer of tile that got it to a total of just about 12". We added 2X4 cross member underneath to assure the toilet was adequately supported. The shower didn't require much additional support, as it was a one piece unit.



If you have a "3 meter ceiling" platforming just the toilet and surrounding 12-15 inches would probably give you the drop you need, if you have the space around the toilet. Sort of a throne thing, I guess.

Answer 6

I'm not a plumber, so do not want to give you any figures, as may be wrong.

However, If I was in you situation, I would contact at least 3 plumbers, ask them a quotes and ask many questions of things you don't know such as "would you need to raise the floor to get the right angle?... Aren't we too far from canalisation?..."

Once you've all the answers, then you can do it in DIY if you wish, with professional advices for free. Don't tell them you only want advices, tell them you want a quote.



I always go for at least 3 trades people, as there's always the rogue trader in there, and you want at least 2 saying the same thing to confirm it's right.



But due to your circonstance, you may have to use professional rather than DIY

Answer 7

I've checked the Building Regs. which say that a wc branch may be 6m long with a fall of 18 to 90mm per metre run; a wash hand basin can be up to 1.7m for a 30mm dia. branch, 3m for a 40mm branch or 4m for a 50mm branch [baths similar]. These figures apply to non-vented branches, which is what you will have in a block of flats [unless you're the top floor].

Answer 8

Usually the drop is 1:40 to keep the solids moving.

So 13ft needs about a 3" rise. Don't know about the proximity requirements though

Answer 9

Just put the pipe on the outside wall

Answer 10

Saniflow will work with negative head, it is capable of pumping vertically about 3 metres, I believe they have a system where ALL water and waste is capable of being pumped horizontally of even raised,

Suggest you pursue on Google for Saniflow.

Answer 11

Rule of thumb is 1/4 inch drop for every foot of run.

Answer 12

the normal fall for a soilpipe is one in forty to be self cleansing ....you will need to box and sounproof the pipe