Thoughts on where to put utility drain/pipe work

jonnydeppiwish!

Hi
I’m after some advice please 🙏 

I’m in the middle of converting my garage - the front half is a small study area and the rear is a utility room. For the water feeds I come down from the bathroom above the rear of the garage, inside the studwork then along the left wall. This was the easy part.

The bit I’m struggling with is the drain pipe work and where to route it through. The WM, sink and TD will be on the left wall at the rear of the garage. The nearest drain points are either the wall outside of the toilet (which would mean routing the pipe work around the outside of the study so it would need boxing in), or at the rear of the kitchen (to the right of the sink, and then into the garden).

I can’t go through the garage floor as I’ve left it too late (flooring glued etc), which way would you go?

thanks

grumbler

Do you realise that a waste pipe must have a certain gradient, that can be a problem if the route is too long? This have to be a starting point of any plan, not finishing.

I don't like your plan A and don't understand the plan B - "at the rear of the kitchen (to the right of the sink, and then into the garden)."

flashg67

I can't see an easy route unless you can rearrange where the appliances will go and run the waste into the entrance and / or WC room. Does running it to the kitchen waste give a steep enough fall for the pipe? Otherwise digging out a new drain point outside is an option, but aa much bigger job!

getmore4less

Where is the upstairs toilet down pipe?

No wash facilities in the downstairs toilet?

New layout would help with current plumbing routes.

jonnydeppiwish!

getmore4less said:

Where is the upstairs toilet down pipe?

No wash facilities in the downstairs toilet?

New layout would help with current plumbing routes.

That would be the easy option but it’s inside of a supporting pillar, plus it’s an asbestos pipe to boot.

jonnydeppiwish!

flashg67 said:

I can't see an easy route unless you can rearrange where the appliances will go and run the waste into the entrance and / or WC room. Does running it to the kitchen waste give a steep enough fall for the pipe? Otherwise digging out a new drain point outside is an option, but aa much bigger job!

It should do - it only really needs a drop through the kitchen floor over 3m. Prior to this I can keep I up relatively high under the stairwell 

jonnydeppiwish!

grumbler said:

Do you realise that a waste pipe must have a certain gradient, that can be a problem if the route is too long? This have to be a starting point of any plan, not finishing.

I don't like your plan A and don't understand the plan B - "at the rear of the kitchen (to the right of the sink, and then into the garden)."

The first option would be the easier but possibly not so good looking on the front of the house as I’d need a pipe running in front of where the garage door was, spanning about 2.8m.  I can put it in the stud wall from the rear of the garage.

definitely know it needs a gradient - have also though about a pump ie Sami vent to direct it straight back where the water feeds have come from and into the shower waste of the upstairs bathroom

jonnydeppiwish!

The external drain at the rear is in the external corner of the conservatory and the rear wall with the window