Joing soil stack

[microkid]

i am about to cut my soil stack at about 1 meter high. and then replace everything above this point. my question is joining the new pipe to the old pipe. I have bought some floplast pipe and notice it isnt quite teh same diameter (a few mm dif). Can I push the old bit of the pipe into the flared end of the new pipe? Its kind of against the flow to the way the other joints go. not sure if his is ok?

 

[muggles]

You haven't said what your original stack was made out of, but any joints that cause a restriction are a bad thing

 

[microkid]

Its grey plastic. I am unsure of the brand but it seem sto be 110mm. I want to fit 110mm floplast black using a coupler http://www.screwfix.com/p/black-double-pipe-coupler-sp105/47977 between them. is that going to be ok?

 

[JimLoskot]

why not dig down a bit and replace the lot onto the (presumably) clay pipe

 

[microkid]

seems to go into concrete

 

[picasso]

This will do what you want View media item 47384

 

[microkid]

can you use those above ground?

 

[picasso]

can you use those above ground?

of course you can.

 

[microkid]

whats wrong with this: http://www.screwfix.com/p/black-double-pipe-coupler-sp105/47977

 

[tryitandsee]

You would normally have a female to male connection so that the male points downwards and female upwards, this helps to avoid leaks at the joints.

Your grey soil ideally should be joined at a collar with your new black soil, ie black pipe end (male) into grey collar (female).

For what you are trying to do, you may just get away with it with your suggested double joint, but you must realise it's the wrong way to do it. Having said that the join is normally quite good.

Have seen larger plastic collars that have two large stainless steel jubilee clips that are used for joining underground, perhaps that would be better.

www.fernco.com/plumbing/flexible-couplings/stock-couplings

found this , gives you an idea what I'm on about

 

[tryitandsee]

Make sure you start from the join and go up with your black soil ending with a collar, so you can either add a fitting or more pipe. Hope that is making sense. Always male to female, work it out before you cut pipe

 

[microkid]

if i pull the grey pipe apart at one of the couplings could i then push the black pipe back into the old grey coupling or will it not seal? Failing that could i not use solvent to bond a joint?

 

[JimCrow]

if i pull the grey pipe apart at one of the couplings could i then push the black pipe back into the old grey coupling or will it not seal? Failing that could i not use solvent to bond a joint?

yes it will seal, chamfer the pipe end and a bit lubricant on it .

 

[microkid]

You would normally have a female to male connection so that the male points downwards and female upwards, this helps to avoid leaks at the joints.

Your grey soil ideally should be joined at a collar with your new black soil, ie black pipe end (male) into grey collar (female).

For what you are trying to do, you may just get away with it with your suggested double joint, but you must realise it's the wrong way to do it. Having said that the join is normally quite good.:

Just following on from this... I have noticed that a lot of the joints on sale such as elbows, T pieces, etc... have double entry so that would mean one side is always wrong?

Also when running a short piece of pipe between two connections (say 500 or less mm) does taht mean I have to a long length with the coupling at one end just so I can fit it the correct way?

 

[microkid]

if i pull the grey pipe apart at one of the couplings could i then push the black pipe back into the old grey coupling or will it not seal? Failing that could i not use solvent to bond a joint?

yes it will seal, chamfer the pipe end and a bit lubricant on it .

So If I pull the top section of the joint shown in this picture out and replace it with a new piece of black pipe with a chamfered end using lube when inserting it will seal again ok? The joint was probably first made in 1998 so it’s been undisturbed for 14 years?

If so how do I separate the joint easily? without pulling the bit in the ground out?

I need to shortened the section I am removing so even if I cut it down I will end up without a socket on the end so my coupling will be the wrong way.
View media item 47659 [/img]