Joining pitch fibre drain

[mogget]

I'm not sure whether this should be in plumbing or building, so I'll try here first.

At my house there's a gulley which has never drained properly, so today I've dug up the path around it, to find this:

Untitled

• mogget
• 17 Feb 2009
• 1

The clay pipe from the gulley wasn't connected, which would explain it not working!

The black pipe has a small label on it that says it's 'pitch fibre', and was encased all round in concrete. The pipe is approximately 115mm in diameter, and serves my house only. It's a combined foul / rainwater system. I'd like to replace the original gulley with a new plastic roddable one, and tee into the pitch fibre pipe.

So, the questions -

1) how do I cut it?

2) what fittings / adaptors should I use to tee into it?

3) does it contain asbestos?

I'd be grateful for any help with this.

Thanks,
Mogget

 

[swidders]

"Pitch fibre is made of wood cellulose fibre impregnated with carefully refined inert coal tar pitch, under vacuum and pressure (about 25% fibre to 75% pitch by weight)."

You have do doubt researched this far, and discovered the pitfalls of it, which is of no comfort I know.

Cut with angle grinder is probably less likely to damage it by compression of other means, I'd have thought.

If it were me, I'd try to insert an offcut of 110mm with sealant, with the tee and adaptor already on, with enough further pipe on it to,er, concrete around to avoid further disturbance. (But I never said that!!!!!) Then jubilee it down a bit.

Ok, I'm guessing, but at least I'm trying!!

 

[Hugh Jaleak]

Would suggest you cut carefully with an angle grinder. Joint 110mm plastic to existing pitch fibre with a flex seal coupling or similar of appropriate size. Peagravel bedding around and above the pipe for protection before backfilling.

 

[swidders]

Would suggest you cut carefully with an angle grinder. Joint 110mm plastic to existing pitch fibre with a flex seal coupling or similar of appropriate size. Peagravel bedding around and above the pipe for protection before backfilling.

Of course peashingle - like I said, I never even mentioned concrete

Would be worried about existing pipe collapsing with unsupported flex seal

 

[doitall]

Hacksaw or old hand saw will cut it much better than an angle grinder.

The heat will just clog the blade up.

You can use a Fernco coupling if anything,

 

[Hugh Jaleak]

Have to admit ive never come across this stuff in the 'flesh' before. I didnt realise actually how weak it is. I presume the concrete then protects the pipe from collapsing.

 

[doitall]

Have to admit ive never come across this stuff in the 'flesh' before. I didnt realise actually how weak it is. I presume the concrete then protects the pipe from collapsing.

That's the plan in actual fact it's just as strong as the old clay

 

[swidders]

Have to admit ive never come across this stuff in the 'flesh' before. I didnt realise actually how weak it is. I presume the concrete then protects the pipe from collapsing.

I'm suggesting getting a piece already partly fabricated, connected to it, which is then concreted into place afterward (away from the fibre pipe) to prevent disturbing the joint while connecting to the new pipework.

Wouldn't consider is wise putting concrete onto the fibre pipe since, if joint fails, will be up the creek. If the new piece of 110 offcut only is partially cemented in, at least it gives a fighting chance to remove to rectify it.

 

[swidders]

Have to admit ive never come across this stuff in the 'flesh' before. I didnt realise actually how weak it is. I presume the concrete then protects the pipe from collapsing.

That's the plan in actual fact it's just as strong as the old clay

While researching, there's a lot of mention about it collapsing all over the place and having to be re-lined.

 

[doitall]

That's why you bench it with weak concrete. Pea gravel is for plastic pipes

 

[mogget]

"Pitch fibre is made of wood cellulose fibre impregnated with carefully refined inert coal tar pitch, under vacuum and pressure (about 25% fibre to 75% pitch by weight)."

You have do doubt researched this far, and discovered the pitfalls of it, which is of no comfort I know.

That's more detail than I could find - must have put the wrong words into google!


You've all confirmed what I suspected, which is that this stuff is a nightmare! To complicate matters it's only a few inches below the surface, so it looks like I'll have to make the best of it. I can't afford to re-do the whole lot, and it will probably be going in the same way it came out, with concrete. It does seem to be holding up ok and hopefully I won't have to spend hours chipping away at it with the SDS chisel again.

Nice to know it can be cut with a saw

Thanks everyone for your help, and here's a random link about pitch for anyone who's interested...

http://www.physics.uq.edu.au/pitchdrop/pitchdrop.shtml

 

[swidders]

Am going to watch the ninth drop live!!
Anyone taking bets?

 

[mogget]

Am going to watch the ninth drop live!!
Anyone taking bets?

Blink and you'll miss it!

 

[swidders]

Blink and you'll miss it!

One long blink.

Good luck with the nail file to cut through that pipe.

 

[swidders]

That's why you bench it with weak concrete. Pea gravel is for plastic pipes

Thanks for the info. So the pipe is mainly for waterproofing, and concrete for structure?