Re-laying damaged drains

mazza

Hello all,

We've had recurring problems with one of our drains getting blocked. We've worked around it for a while, but the time is coming for serious action to resolve it. I'm still trying to figure out what to do, so any thoughts Boardsie's may have would be great!

Basically there is a c 3m length of drain (into which toilet, sink, shower etc empties) which is made up of lengths of ceramic pipe, probably laid in 1970. Over the years these seem to have moved slightly sideways, so they don't fully line up any more. Some kind of ground movement, I guess... Anyway, there are lips at the side and on the floor of some of the pipes where they join and toilet paper etc get stuck on these causing repeated blockages! Nice.

We know all this as we had a camera survey done by Dynarod during the last blockage. They have suggested relining the pipes without digging up: about 2k worth of work with no guarantee blockages won't occur again.

The more permanent solutions I can see are:

1) Digging up affected section of drain and relaying it.

I assume this would involve replacing the ceramic pipe with a plastic waste pipe - could someone confirm please?

Also, is this a job for a plumber, a builder or a specialised drain company. (I'd be happy enough to do the digging - the unskilled bit! - but would need someone else to lay the pipe correctly, so it wouldn't cause more problems.

Anyone had this type of work done before and have a recommendation of a company who would do this reliably please?

2) Installing a Saniflo on the current toilet to make all waste going down the drain liquid and therefore clear without blockage.

Maybe this is only a temporary workaround too though and the existing drain will eventually fail / leak if / when the pipes come apart? I've read some general reviews of Saniflo's but should I be even thinking about it in this case?

3) Something else?

Sorry this post is so unfocussed, but anyone got any thoughts on the options?

Thanks a mil,

Maz

ircoha

Dont know anything about re-lining so cant comment.

Depending on the depth the pipes are at, and if the overburden is clay rather than concrete, digging and relaying is not a big job, have u access for a mini digger to do the hard bit?

It is a job for a builder as opposed to a specilaist plumber, especially of the trench is dug: the slope is 1:40 and 3m is nothing.

The bedding for the new piece of wavin is important, dont have an online ref but the home bond manual does say how to do it.

In terms of the toilet paper/etc: nobody using these baby wipes or the make-up removing wipes by any chance: just asking as that is a problem we have in a run of 4 houses, new neigbours in the end house and they use 100's of them:(

mazza

Thanks for the info, Ircoha!

Part of the drain goes under the house walls etc, so although its a pretty short dispance, its potentially tricky.

I've had one company out to look at it and they have suggested laying the new pipe down a different route to digging around under the house etc. A couple more are due out to give quotes as I'm really not sure about doing this as a DIY job...must check out the Homebond book you mention tho'.

The problem definitely isn't being caused by stuff like you mention being flushed. We're ultra-careful about what goes down after all the problems, so I really think it is being caused by structural defects identified by camera survey of the drain.

Thanks again.

Martron

if it was not deep you could to it yourself no problem.

you can get a rubber coupler that connects on to existing pipe from the house to your new 110mm plastic pipe. all you need would be one length of the new pipe.

is this connecting into a septic tank or a main line sewer on the street? as you may need another coupler to connect back onto the main line.

dig the pipe out by hand it will be hard work but it cant be done. keep in mind that the soil has probably been contaminated with sewerage so you will need gloves and eye protection.

assuming that the pipe is going in a straight line there will only be one lenght so remove old clay pipes. place the new pipe in the ground.

ensure there is a good fall on the pipe. 1:100 is the shallowest fall i would recommend ( there will be good force of flow coming from the house) you can tell it 1:100 if you get a metre long spirit level and tape a 10mm spacer to the end of it. then put on top of your pipe and if the spirit bubble is level you have a 1:100 fall. obviously if the fall is greater than this its no harm.

back fill of the pipe is very important as you do not want the pipe to sag and also i dont know what type of traffic will be over the pipe.

you can get readymixed bags of dry concrete mix. this is gresat stuff for packing around pipes.

so basically pack under the pipe ensuring that you do not disrupt the fall.(check with the level after packing) then cover the pipe with the same mix compacting as you go. now you will want to fill the hole with as much of the contaminated soil as you can keeping about 200mm from the surface where you will you clean soil.

hope this was of help. but will need to know what traffic and how deep the pipe is but this is general guidline