Dear all,
I'm hoping that this is a fairly staright forward question, but I wanted to clarify with the experts anyway !
I have recently discovered a crack in the sewer pipe that runs under our patio.
I have excavated all around the pipe and it seems that there is a crack all around the 'knuckle' of the pipe (knuckle being where the pipe seems to get wider, I assumed to join to another pipe/insepction chamber). The crack is approx. 3' from the drain.
Should I replace the whole section of pipe, or is there an easier (but just as effective) way of repairing the carck ?
The cracked pipe is not used for fowl waste, it just has dirty water from a washing machine running through it.
Any help on this matter would be most appreciated.
Thanks,
Simon.
Repairing cracked drain
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danensis
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First of all, you do need to repair the crack. I have seen houses subside as a result of washing machine waste (grey water) running under the footings.
Most of the techniques I know require either getting inside the pipe, or having one loose section. There are a number of cowboy techniques - running a cement slurry into the pipe and leaving it to set is a favourite. You need the slurry stiff enough not to run away quickly, but runny enough to fill the crack when it reaches it. Jusging this can be tricky.
I have also repaired a pipe joint using a sheet of stiff card buttered with araldite, but don't tell the BCO about that one! Eventually the card rots away but by then the araldite has sealed the gap.
The official way is to break out the length of pipe, then use a rubber coupling and two jubilee clips to cover the broken joint.
Most of the techniques I know require either getting inside the pipe, or having one loose section. There are a number of cowboy techniques - running a cement slurry into the pipe and leaving it to set is a favourite. You need the slurry stiff enough not to run away quickly, but runny enough to fill the crack when it reaches it. Jusging this can be tricky.
I have also repaired a pipe joint using a sheet of stiff card buttered with araldite, but don't tell the BCO about that one! Eventually the card rots away but by then the araldite has sealed the gap.
The official way is to break out the length of pipe, then use a rubber coupling and two jubilee clips to cover the broken joint.
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flowjoe
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It sounds as though you have VC (vitrified clay) pipe work, which is basically earthenware pot it is prone to stress fractures like the circumferential crack you describe. Fractures are common because granular fill was not used on installation and I am afraid if there has been movement there are likely to be further fractures.
If its several metres from the house then there should be no major affects with regard to you foundations, that is not to say that the pipe work wont carry on moving due to water loss over the next twenty years, as always there are methods for surveying the system to find the full extent of the problem (if there is one) prior to any repair works being undertaken, you might even find you are covered on your bricks and mortar insurance for the works required.
If its several metres from the house then there should be no major affects with regard to you foundations, that is not to say that the pipe work wont carry on moving due to water loss over the next twenty years, as always there are methods for surveying the system to find the full extent of the problem (if there is one) prior to any repair works being undertaken, you might even find you are covered on your bricks and mortar insurance for the works required.
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Tony McC
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I'm intrigued by the statement that the broken pipe doesn't carry foul water, just dirty water from the washing machine .... that is foul water!!
From your description it sounds as though you have a break at the collar of the pipe. If water is escaping via this crack, then it should be repaired. The simplest way of repairing shallow pipes (as I assume this is) would be to cut out the break to around 300mm each side, so that you have "good" pipe at each end, and then use reapir couplings (or even the sliding couplings) to insert a new length of pipe. It's a technique very similar to that shown on the Making New Drainage Connections page.
From your description it sounds as though you have a break at the collar of the pipe. If water is escaping via this crack, then it should be repaired. The simplest way of repairing shallow pipes (as I assume this is) would be to cut out the break to around 300mm each side, so that you have "good" pipe at each end, and then use reapir couplings (or even the sliding couplings) to insert a new length of pipe. It's a technique very similar to that shown on the Making New Drainage Connections page.
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