WC into understairs pantry - nightmare

[advisewelcome]

Hi, looking to do two projects:

PROJECT (A): Want to bring garage WC to below the stairs pantry
PROJECT (B): Then maybe turn the garage WC area into a shower room

Pic of the PROJECT (A) basic move:

Pic of the garage WC:

Pic of the pantry area:

Garage WC and Pantry on either side of the same wall with the Garage WC being a step down:

Further pics and details here:
https://photos.app.goo.gl/GtCgH2a9YbByReJy8


First step is PROJECT (A) and its a nightmare tyring to find one person/company to do this at this time.

So working out what I can do myself and the plumbing is the main issue so hence posting here. Can post elsewhere if needed:


I think the steps to do PROJECT (A) is:
1 Get the plumbing in for the new WC by extending waste through the wall
2 Plumb in the feeds for the WC and small sink
3 Fix a stud wall for the cistern and pan to sit against
4 Do the pantry floor
5 Plumb and bolt in the WC
6 Plumb and fix in the sink
7 Fix an ventilation fan
8 Make a door into the hallway
9 Stud wall where the current door is

These steps make sense?

Anything I am missing or anything else worth considering?

Welcome feedback, will have questions. Ta!

 

[Bonni]

Just add to your list - Altering the toilet waste pipe requires building regs.

 

[advisewelcome]

Thanks for the reply.

Do you think it will be a hassle extending that old waste into the pantry? I think its a 110mm pipe extender - the plumber scared the heck out of me by saying that pulling out the old Garage WC from the clay floor collar, could present all kinds of issues - e.g. if the clay waste pipe breaks they would have to dig up the garage floor and replace that part of the pipe?

... is that possible and does it happen often? Or does the old WC generally come out easily and new extension waste piping just plug in?

A shower that will sit over that waste plumbing in the future, so would want to avoid smells and leaks.

Appreciate any thoughts.

 

[denso13]

Do you think it will be a hassle extending that old waste into the pantry?

It depends.

A shower that will sit over that waste plumbing in the future, so would want to avoid smells and leaks.

You'll need to dig down and make a connection to keep everything below floor level. What type of connection depends on what you find.

 

[advisewelcome]

Oh, what am I getting myself into here...

From what I am reading, I guess the WC pan is cemented into the house clay soil pipe and can get thus broken when being removed?

There will a wooded raised floor put in about 2 bricks up to make the garage floor level with the rest of the house...

So, I think the new waste pipe connection to the clay collar will be mostly under the raised wooden floor...

The u bend bit will stick out above it and then go into the pantry WC, I think this is 110mm diameter.

The plan is to put a plinth for a shower tray there and that should cover the u bend bit in the garage room which is about 110mm high. I assume this will also be needed for the shower plumbing to feed into that waste and maybe a sink waste if its fitted in the garage shower room. Not sure how that plumbing will go together.

So if the connection to the house waste pipe will be under the raised wooden floor (if you get what I am saying) - would I still need to dig things up? - or can I just get the waste extension fitted to the collar sticking out of the current floor?

 

[denso13]

Would I still need to dig things up

Yes, you'll need a proper connection onto the clay pipe. Doesn't need to be deep.

 

[Hugh Jaleak]

Biggest risk will be removing the existing Pan without doing too much damage to the soil pipe, if you're lucky, it may break the collar off the clay pipe with the pan, leaving rest intact. Alternatively, you'll have to break the outlet of the pan away, piece by piece, (wear stout gloves, broken porcelain is razor sharp!), and once the pan is off its base, use a Dremel or suitable cutting tool to carefully cut around/through the pipe, under the collar/above the floor to remove the rest.

Then, if the pipe looks ok, (no sign of damage or cracking), use a suitable connector, to take you from the clay to 110mm plastic, go through the wall at a suitable height to meet outlet of new pan. McAlpine offer a version which also has a 40mm boss connection for your proposed shower and basin. https://mcalpineplumbing.com/plastic-chrome-fittings/drain-connectors/drain-connector-with-boss/ (Screwfix stock it , other suppliers are available. )

Digging the floor up is a last resort!

 

[cdbe]

Surely you'd be better knocking through and making a combined WC/shower room? No one wants to take a dump then run round the house to get to the shower.