Why does my house have a SaniFlo and is it going to be possible to remove it?

greensalad

Just bought a house. Originally bungalow with upstairs dormer conversion completed in 2011. It has SaniFlo for the upstairs bathroom (en suite and shower room). We knew it had them and thought we'd just have to see how they went and hopefully replace them at some point. One is fine but the other is terrible, blocked up three times already and as it's in the shower room means we cannot shower when it's blocked. Last two times it fixed itself (eventually drained) but this time has not done so.

What we want to understand is why was the SaniFlo put in in the first place, and is it possible to redo the bathroom (something we want to do anyway) to include a normal toilet? I had a builder round for a different job and mentioned it to him, he had a look and couldn't understand why the SaniFlo was added and not a normal toilet. 

This is the bathroom layout, with a small access cupboard behind the toilet:



You can see the SaniFlo pipe going off out to the back of the house:



Comes out of the back of our house and is pinned down the side into our soil stack. The stack sits much further out from the rest of the house due to the fact there is a 1970s extension on the back of the property, and the drains were moved at that time (as evidenced by some old drawings we discovered). Offending bathroom window is on the left upstairs:





Any ideas why the SaniFlo was added? My guess is soil stack too far away from the house? Any ideas on how to change that? We'd like to, in the future, build an extension to replace an old conservatory that would fill in this "nook" where the SaniFlo pipes emerge from.

Section62

greensalad said:

Any ideas why the SaniFlo was added?

Generally because it is easier for lazy builders/penny-pinching homeowners to route a 40m pipe from a SaniFlo rather than a 110mm soil pipe.

In this case there's no obvious reason why it couldn't be changed to conventional drainage, but it would involve some thought to the best route, and probably some digging up of floors (so mess, noise and disruption).

greensalad

Ok so seems like it is not going to be a complete no-go to sort out. We were hoping to redo the whole bathroom anyway (as it’s a bit old and ropey and also not to our tastes) but we thought we might be able to put it down the long list of jobs required in this house. Sounds like a full bathroom refit will be prioritised then. 

Do you have any idea what the solution for the waste-out would be from there? I’ve been reading a lot about the compliant angles and such and it’s all a bit confusing!

TELLIT01

The rear single storey section looks like a later extension so there would have been a bathroom, with proper waste system in the original property.  If you can work out where that was, you may be able to determine where the drain runs and get a proper waste pipe to link in.

NSG666

Is the bathroom the window on the left of your photo? If it is then what is at the other side of that extension? i.e. do you have access to run a new underground drain to the (gable end?) ?

It needs a proper site survey though to make sure the solution covers both bathroom and en-suite. What did your builder say could be done?

greensalad

Sorry I thought I'd explained with the pictures but I'll add some more detail. Builder didn't really comment beyond "it doesn't seem impossible" as he was here on another job quote. 

The downstairs bathroom from the original 1965 build is still here. It's a downstairs loo with utility area where the bathtub would have been. It is located pretty close to the offending upstairs bathroom. Above the original downstairs bathroom is the hallway that leads directly to that bathroom. We are planning to recarpet that area so if a soil pipe did need to come out of the upstairs bathroom under the floorboards at all that would be doable. 

The 1970s extension on the back had a bathroom added too (since stripped out) and the original plans below show the drain location. There is a gulley directly at the original downstairs bathroom back wall, and then the soil stack is further out.

The other side of the extension/house is our access path and then a few miles of forest! No neighbours on that side. I don't think we could do much with that side of the house... although we have access the drains aren't on that side so nowhere to dig through without digging under the house.