New ic next to existing manhole

[gedger]

I'm a keen DIY'er and am converting a integral garage to a bedroom and on-suite.

My first phase is to install the foul water drains to the loo and shower cubicle. The outside wall runs parallel with the existing drain and a manhole is right next door although it has no space to put any additional connections.

My plan was to install a new uPVC IC next to the existing manhole and then connect to the clay pipe using adaptors. Having now exposed the pipe I discover that it is cracked right next to the existing manhole see link below.

http://manorfields.homeip.net/showimg....ain.jpg

I want the new IC as close to the existing manhole, any suggestions on how to proceed?

Initial thoughts are to remove the broken clay pipe from the manhole (is this possible with out breakage?) and insert an adaptor to plastic and then carry on as before.

Thanks for any input.

Richard

PS. Thanks for the great website.

[84-1094545549]

This 'break' is typically encountered when manholes and other heavy ICs built from brickwork or concrete sections do not have short 'rocker' pipes linking the main pipe run to the manhole block. The rocker pipes allow movement of either the MH or the pipework, without cracking the line. What has happened on your MH is that either the MH or the pipe (most likely the MH) has moved or settled over the years, and because you have a rigid pipe, its only option was to break.

The problem is compounded by the fact that the collar of the pipe entering the MH is tight up against the brickwork - there's no room to make a new connection.

With older salt-glaze pipes, you can sometimes get hold of a uPVC adapator-lining that slides inside the existing pipe and provides a connection for the new uPVC drain systems, but it's not always possible, just depending on the type of pipes involved. Judging from your photo, these are old HepSleve pipes, rather than salt-glaze, so the adaptor lining option probably won't apply to you.

The only fix is to remove the light-coloured pipe by sawing through it as far away from the MH as is possible. this will leave a short piece of the pipe mortared into the collar of the pipe projecting through from the MH. Now comes the critical bit - you need the skill of a surgeon to try to remove the remaining piece of pipe from that collar, without breaking the colar. A small nangle grinder is awfully usefiul at nicking the pipe, and then you need to very carefully chisel out whatever you can.

If all goes well, you should end up with a clean and intact collar to which you can make a new connection. The likelihood is that the collar will break, the break may carry through to the internal MH pipework, and you're left with no option other than the chop out the whole of the pipe and replace it completely. This involves breaking out part of the concrete bed of the MH, seating the new pipe on a bed of fresh concrete and then re-benching. This is a LOT of work.

What's in the MH? In cases such as this, it's often easier to rip out the entire MH and replace it with a new placky IC. I'd be looking to see if this was an option.

[gedger]

Tony

Thanks for the reply, backs up my thoughts although I hadn't considered replacing the whole lot.

The current MH has 3 inputs on the RHS and I'm adding 2 more (also on the RHS) with the new IC so I guess I could replace the whole lot with a 5 input plastic IC and route some of the existing inputs round to the other side. Sounds like more work but could well end up being much quicker to do!! I may well find that other inputs have also cracked so this sounds like the best option.

Thanks

Richard

[gedger]

Why are things never easy?

Having looked at replacing the whole lot I find all the 5 input IC's I've looked at (marley, osma, hunter) all have a 50mm invert depth from the input pipes to the through pipe. This means that the existing pipes in the old MH which are all at the same level need to rise by 50mm which isn't possible.

Oh well looks like I've got to keep the existing MH and try to chisel out the pipe unless anyone knows of a 5 input IC with all pipes at the same level?

Richard

[84-1094545549]

You don't have to lay these IC bases on the level, you know. You can tip 'em back a bit to reduce the 50mm fall to a more realistic figure, and then fettle the raising piece accordingly. As long as there's a touch of fall, so that water doesn't hang in the chamber, that'd be alright.

However, having 5 inlets on the RHS is a bit of a bugger. I'd be tempted to build a new chamber using concrete sections. Trying to bring pipes over from the right to the LHS means crossing over other pipes, which is impossible given the existing levels.

Your other option would be to 'double up' - use 2 immediately adjacent ICs to create sufficient inlets....

[jones2004]

Leave a few inches of the light coloured pipe sticking out of the rocker. Then with a brickies hammer tap the light coloured pipe until it cracks and remove from the rocker then gently remove the mortar, if the rocker pipe begins to crack (The collar bit of the rocker will usually be the only bit that cracks)cut flush with the manhole wall. If you have managed to remove light coloured pipe and mortar get a 4inch plastic pipe connection and stick a pipe in one end and cut flush to the collar. Then the side where the plastic pipe is inserted push into the rocker and use extra rapid mortar to make the connector flush with the channel inside the manhole. If you have to cut the rocker flush to the outside wall of the manhole do the same with the collar and push flush against the rocker pipe and secure with extra rapid mortar. If you have trouble holding the collar whilst packing with motar use a 4inch inflatable bung inbetween the collar and rocker pipe this should help.

Im not sure if you can make sense of it all, but it should help!