Can we put an extra loo here? Pictures

[NinNinJin]

From looking at this plan do you think it is possible to put an extra loo at the basement level and how? Is it too complicated? It is a typical terraced house.

There is a washing machine in the kitchen corner. It has drainage.

Just looking at a potential house and trying to work it out. Would appreciate your thoughts ☺️

And a photo of a random similar house to give you an idea. I'm sure you have seen them

Where would you want it? Thing with the loo is that it doesn’t just need water you need to connect it to the soil stack which looks like it comes down the front corner of your house. So unless you wanted it in the front right hand corner (where the existing bathroom is) you’d have to do a connection to the soil stack from the new location, which is a big job anyway but probably even more difficult in a basement. You could get a loo with a macerator which wouldn’t require such a big connection but these are absolutely notorious for malfunctioning and either not flushing or leaking poo!

Best bet is to get a local builder to look at it or ask your neighbours if anyone else has done it and how (or check Rightmove for sold floorplans).

I agree that a Saniflo type of toilet would probably be easiest, but they can be a nuisance, especially if it's going to be used a lot. You should have it serviced annually to avoid the macerator blocking up, that's what causes the floodings. It's honestly gross when it happens. If it's going to be used very occasionally you might be fine with one though.

@Heronwatcher @Snoken hmm def doesn't want anything disgusting. I'm even thinking by of smth like this. Just for the guests to use if we have a barbecue outside and for kids to run to if they have an emergency/playing in the garden.
Would we need any planning permissions for this?
That would be somewhere near the pipes I reckon. Since the loo/bathroom/kitchen sink are nearby.

If I remember correctly, the reason a lot of basement toilets are macerators is because you can't get enough of an angle on the waste pipe as it's too close to it, for larger items to flush away. So it could be fine for a sink where you only use liquids, but not a toilet. That's why the things your flush needs to be macerated first so it flows better. I think if it is only going to be for very occasional use and you can trust your kids not to throw wipes or anything other than toilet paper down there you would be fine with a Saniflo and if you have it serviced annually it probably wont ever overflow.

I have a friend who has a saniflo toilet in her basement, it gets used maybe 2-3 times a week, and she hasn't had to service it once in the 3-4 years she has lived there. So it all depends on the usage frequency and that the people using it doesn't try and flush down tonnes of paper or anything else.

My opinion on whether this is feasible is whether it can plumb directly into the existing soil stack or not.

I wouldn't touch a saniflo (macerator) given personal experience of them. You have to treat them virtually like religious objects to stop them failing, and most plumbers won't touch them due to how minging they are. Maybe I would consider one if I was the only person using it and even then only for very occasional use.

As someone who has had a saniflow toilet in their property for many years, I would avoid them.

I shouldn't really have posted about the Saniflo without mentioning this classic post, on uk.d-i-y, from almost 25 years ago:

https://wiki.diyfaq.org.uk/index.php/On_the_Subject_of_the_Saniflo

Where is the drainage pipe that connects to the sewage pipes? Below basement floor level? Or above? That’s the most important consideration.