90 Degree Flexible Waste Pipe

[cwhaley]

Just plumbing in a new downstairs WC in a small extension. Stud walls are up, water feed is connected up and ready to supply the toilet and washing machine but I've hit a bit of a problem working out how to deal with waste from the toilet...

The toilet will be backed up against the rear of the house, with waste needing to exit 90 degrees to the right and straight to the outside where the existing soil stack is.

To the rear and right of the toilet is the water supply to the extension which I will box in (as you'll see on my simple diagram attached), but this means it may be in the way of the waste pipe so I've opted for a flexible waste pipe by McAlpine.

If I go for the attached, what do I need to connect this up to a standard 4" waste pipe which will be going through the cavity and connected up with a boss to the existing soil pipe?

https://www.screwfix.com/p/mcalpine-macfit-mac-8-90-wc-short-pan-connector-white-90-112mm/89461

 

[oldbutnotdead]

Prayer. You'd be better with a standard 90 degree adaptor on the loo and a couple of adjustable bends & some pipe to get outside. Flexis are not a good long-term solution.
EDIT Just reread- you've already got a rigid trap adaptor (good), couple of thesehttps://www.toolstation.com/adjustable-bend-110mm/p73512 and a length of tube is what you want

 

[cwhaley]

Prayer. You'd be better with a standard 90 degree adaptor on the loo and a couple of adjustable bends & some pipe to get outside. Flexis are not a good long-term solution.
EDIT Just reread- you've already got a rigid trap adaptor (good), couple of thesehttps://www.toolstation.com/adjustable-bend-110mm/p73512 and a length of tube is what you want

Yes even just for aesthetics, I wanted to avoid having a piece of completely flexible pipe as I imagined it'd look like a tumble dryer vent pipe.

Thanks for the link, I had tried searching for something like that but wasn't sure if it was appropriate for my proposed fitting. Would that fit into the end of the pipe I linked on my first post? I imagined jubilee clips so just trying to understand how the connection is made!

 

[Hugh Jaleak]

You'll need the Soil (Above Ground) Version, Adjustable Bend 0-90° Grey (toolstation.com) or use 2x 45° bends to 'dogleg' the soil back from the corner. Either way, the Pan Connector you've Linked to has the 'finned' end, which pushes inside 110mm pipe, so you'll need to insert a short piece of pipe into the socket of the bend, then insert the Pan Connector. Make sure it is adequately supported.

Flexis are always best avoided, but a particular issue in Ground Floor application can be the flexi section is translucent. This can attract rats as they see the light and head for that area looking for a way out. Given their need and ability to chew anything and everything, (I have even seen them go through 12" thick reinforced concrete!), they will go through a flexi connector with ease.

 

[cwhaley]

You'll need the Soil (Above Ground) Version, Adjustable Bend 0-90° Grey (toolstation.com) or use 2x 45° bends to 'dogleg' the soil back from the corner. Either way, the Pan Connector you've Linked to has the 'finned' end, which pushes inside 110mm pipe, so you'll need to insert a short piece of pipe into the socket of the bend, then insert the Pan Connector. Make sure it is adequately supported.

Flexis are always best avoided, but a particular issue in Ground Floor application can be the flexi section is translucent. This can attract rats as they see the light and head for that area looking for a way out. Given their need and ability to chew anything and everything, (I have even seen them go through 12" thick reinforced concrete!), they will go through a flexi connector with ease.

Ah that makes sense, I just couldn't understand the method of connection at that 'finned' end. So if I cut a small length of 110mm pipe and push the pan connector into that, then in turn push that pipe into an elbow that will then make a secure connection?

I think I'm going to go for two adjustable 45 degree bends so that I can get the best off-set to avoid the pipes in the corner. It only sticks out the wall a little bit but just enough to be in the way.

 

[Hugh Jaleak]

Ah that makes sense, I just couldn't understand the method of connection at that 'finned' end. So if I cut a small length of 110mm pipe and push the pan connector into that, then in turn push that pipe into an elbow that will then make a secure connection?

Yes. Make sure you chamfer the cut end and lubricate the seal before making the joint.

I think I'm going to go for two adjustable 45 degree bends so that I can get the best off-set to avoid the pipes in the corner. It only sticks out the wall a little bit but just enough to be in the way.

You can, but using a pair of 45's will be shorter and neater!

 

[oldbutnotdead]

Trouble with 2 x 45 is the minimum offset is about 100mm which may be a bit obtrusive a as a boxing. The adjustable bends are great for correcting not quite right alignment. Yes use the grey or black

 

[cwhaley]

Been thinking about it all a little more and I think I'm going to stand the toilet off the wall a little -- perhaps using a batten supported to the wall and the back of the cistern. Bit worried about multiple bends in such a short run creating blockages further up the line. The boxing only protrudes from the wall a couple of inches so it won't have to come out far.

Still learnt a bit from the answers on here as at least I'll know how to join the pan connector to the usual 110mm waste pipe. It's still tight on every other front but I should have enough room for a fall of up to 5mm (the run is only very short as the toilet is next to the external wall).

 

[oldbutnotdead]

5mm fall? Long as it's only 400mm from loo to outside pipe you should get away with it...