Freestanding bath, plumbing in the waste from underneath

ashe

We're in the process of getting our bathroom done in early Jan and the bath is the only thing that has yet to arrive. While looking over the job and materials our builder pointed out that the bath has a waste that drains from underneath, but our joists run the other way (as they often do) to the place the current waste runs along the wall in a boxed up section of the wall. my partner is pretty set on a freestanding bath and must admit I've never been that keen on normal baths with a panel on the side, so short of it being impossible to do, just "not getting a freestanding bath" isn't an option. I'm wondering what happens when people get these fitted usually as this must be a fairly common occurrence?

He didn't seem too phased and said worst case he can add some boxing up just below the ceiling in the hallway downstairs, and run it through that to the soil pipe as we have an internal soil pipe and it runs down the hall wall in a plastered off section. This seems like overkill though and I'd have thought probably easier to create a small raised platform under the bath to allow the waste to drain to where the existing bit does now? If we had external soil pipe I'd imagine it would be straightforward, but bathroom is at the front of the house so don't really want it going out there!

I also read about channelling the joists but sounded like there are some building regs around it so probably not an option either. Normally I'd just leave it to the builder and trust he knows his stuff, but as good as he is he often leaves things til the day and then raises them as an issue. He did our downstairs bathroom and its lovely but there was some mad dashing around on the day to get some things ordered and I'm trying to head off having the same issues to avoid any stress

I'll measure out a floorplan tonight to illustrate. 

GDB2222

I wouldn't notch out the joists for a waste pipe. That's a big notch. Right underneath a heavy bath, full of a lot of water plus people. 

How high off the floor is the existing waste?

Bear in mind that the water needs to run slightly downhill.

GDB2222

And will you have a ceramic tile floor?

ashe

Yeah the floor will be ceramic tile. I'm hoping to get the panel off to check where the existing waste is. It looks to be about 20cm and the existing boxing up that that leads to is 12cm high

GDB2222

If there is some movement, because the joists are weakened, the tiles will crack. I don't think the whole lot will end up in the hall, though.

Some freestanding baths have feet. Effectively the inside of the bath is raised up, and this leaves room for the waste underneath. If it's an acrylic bath, you can easily male a hole in the 'skirt' to get the waste pipe out. You may see it, though, depending how it runs. 

BUFF

depending upon the room you could always consider building a raised platform for the bath - this can work well depending upon the room layout. e.g.
 

ashe

this is the dimensions although this is a smaller version, it looks like 10cm/100mm height from base to where waste is, but not sure if cutting a hole in that would be a good idea to have it come out the back. The more I think about it, the more it seems like it will need to be a raised platform. We do have a cupboard door in the room so it will create issues with that but that is easily solved. 

Doozergirl

Please don't do a raised platform, it's so
obviously contrived. 

Boxing the pipe in on the ceiling beneath isn't ideal but it's certainly less visually and physically intrusive. 
 

Contriving steps up really undermines the point of a freestanding bath.  The short photo you show is incredibly contrived.  Where do those three pendant lights hang in reality?  

Doozergirl

Also, that freestanding has dimensions smaller than a regular bath.  I'd normally
opt for 1800 x 750 where possible. 1700x700 as a minimum.    

Internal dimensions of 1000 X 480 is tiny. It will increase as the bath gets taller, but that bath is about what it looks like, not how comfortable it is to use.

worth checking what you already have and comparing how it might feel. 

Le_Kirk

ashe said:

 While looking over the job and materials our builder pointed out that the bath has a waste that drains from underneath, 

Don't all baths drain from underneath?

ashe

Le_Kirk said:

ashe said:

 While looking over the job and materials our builder pointed out that the bath has a waste that drains from underneath, 

Don't all baths drain from underneath?

Yes, but the current bath has a panel so can drain downwards and along to the boxed in area along the wall. Because it is freestanding, this will drain into the floor not just underneath