I gift this pragmatic solution to the community.

[saveasteading]

I'm very pleased with this pragmatic solution which is definitely not a bodge.

We decided that after 30 years it was time to reduce the internal damp of this crummy extension.

So I planned on 2 days of cutting back the earth fill which was only 2" below dpc.

2 weeks later:

The ground was filled with redundant drain runs, footings and loads of concrete because the working  drains of clay or pitch fibre were at ground level.

It's all working out, but is a long way off proper depths etc.

So I'm faced with forming this connection to  a pitch fibre pipe...(the rest is full of holes in the skip)... the pipe worked only because the pipe was acting as a former for the concrete.

 

Can't break out any more concrete or the pipe will keep breaking. I'm not breaking out the concrete path

Couplers don't fit because there is no protruding pipe.

 

SO. Here is my solution. See the white pipe.

I have cut a 1" lengthways slice out of the short length of pipe so that the diameter reduces and  it squeezes into the pitch fibre. By cutting a wedge shape it expands outwards to be a coupler diameter. 

Tap white pipe further in.

Fit drain pipe over white pipe. 

Duct tape over the slice. Concrete surround.

 

There may be an imperfect joint of white to coupler but that happens in lots of connecters.

I should add that the pipe carries only my workshop sink drain, and leads to the vent riser pipe.

 

I've never had so many 'surprises' in the ground. The perils of refurb.

 

[markc]

Well done, I’ve  seen much worse done by “professionals” 

[saveasteading]

The hammer is there for effect. I had a lad doing most of the graft.

My main role was to stop him overusing the hammer. Some of what was buried shown below.  I bought a Titan breaker which proved to be a good move.

[Jenki]

1 hour ago, saveasteading said:

I bought a Titan breaker

The more frugal tradesman, I know a few, have been laughed at having one of these in a van, but keep the receipt, abuse it, and return it 11 months later for a replacement. My Titan breaker has been going strong for around 6 years now, its changed shape slightly over the years but every year I put some effort in and it comes out looking like new 🤫  

[ProDave]

45 minutes ago, Jenki said:

The more frugal tradesman, I know a few, have been laughed at having one of these in a van, but keep the receipt, abuse it, and return it 11 months later for a replacement. My Titan breaker has been going strong for around 6 years now, its changed shape slightly over the years but every year I put some effort in and it comes out looking like new 🤫  

I have a Titan SDS drill not as big as the breaker mentioned, but can do light weight breaking.  It is over 20 years old, had a hard life but still going strong.  On it's third set of motor brushes and second mains lead (original one was pathetically short anyway)  It only cost about £30 when I bought it all those years ago.

[saveasteading]

1 hour ago, Jenki said:

put some effort in 

I can hardly carry it. 25kg.  Once in place I just have to let it bounce and gently steer it.

 

1 hour ago, Jenki said:

more frugal tradesman,

I was going to hire one but there are few sources round here.

I'm very glad I bought this heavy breaker rather than a lighter one or a drill/breaker as there was more, and stronger,  concrete than expected.

 

I used my battery sds for the subtle stuff to avoid damaging brickwork... also good for slicing clay, ... but it barely scratched the heavy concrete.