Posted: Wed May 21, 2008 6:15 pm
Oh, this job just seems to keep growing 
It started out as a simple blocked gully, then it was a silted and blocked soakaway and now it's a cracked foul drain as well.
In digging up a concrete path to expose the surface water drain that goes to a soakaway, I discovered that a separate (but nearby) foul drain is leaking.
I need some advice about how best to fix it. I've attached some photos (hope the links work OK!) rather than trying to describe what's going on.
The main leak is just at the collar of the 90 degree clay bend where the cast-iron downpipe enters it. I think it had been cracked in a minor way for a while, but wasn't leaking much because it was encased in the concrete of the path. In breaking the path away, I've just made it a lot worse.
There's also a couple of hairline cracks around the flange of the join that's in the middle of the main picture showing the downpipe, the manhole and the interconnecting pipe. It's not clear whether or not these cracks are actually leaking.
What's the best way to fix this?
As I see it, there are a number of choices:-
Presumably I could cut out the damaged area of pipe and repair the breaks using one of those flexible (rubber?) joints that are clamped to the pipe using stainless steel jubilee clips.
I'm a bit concerned about taking this approach because the joint between the clay and the cast-iron downpipe is above ground, so will be visible. The second concern is that, although this drain is close to the house, it's actually under a driveway, so technically could be driven over. Also, the drain is only about 150 mm below the surface. That sounds too shallow to be able to withstand the weight of a vehicle, even relatively infrequently.
I could also replace most of the pipe, but use a flexible joint so that I don't have to break into the benching in the manhole itself. If I go for replacement presumably I could use plastic or clay.
I could also replace the whole downpipe, but I don't really want to do that right now because it will affect the bathroom decor. I'd rather keep this as an 'outside only' job if I can.
So, given factors like a cast-iron downpipe (4.5 inch external diameter) and clay underground (approx 5.25 inch external diameter), the need for a connection between the cast iron and clay above ground, the shallow depth of soil cover, it's driveway location, etc, what's the best way to fix this?
Are there rigid fittings available that enable joints to be made between cast-iron and clay or plastic without having to resort to flexible connectors and jubilee clips?
Given the minimal depth of soil coverage, should I be protecting the pipe? If so, how's the best way to do it?
Any guidance and advice would be most welcome.
Thanks,
Mike
[Edit] I've just noticed that I've been promoted from 'apprentice' to 'digger'. Most appropriate, under the circumstances
It started out as a simple blocked gully, then it was a silted and blocked soakaway and now it's a cracked foul drain as well.
In digging up a concrete path to expose the surface water drain that goes to a soakaway, I discovered that a separate (but nearby) foul drain is leaking.
I need some advice about how best to fix it. I've attached some photos (hope the links work OK!) rather than trying to describe what's going on.
The main leak is just at the collar of the 90 degree clay bend where the cast-iron downpipe enters it. I think it had been cracked in a minor way for a while, but wasn't leaking much because it was encased in the concrete of the path. In breaking the path away, I've just made it a lot worse.
There's also a couple of hairline cracks around the flange of the join that's in the middle of the main picture showing the downpipe, the manhole and the interconnecting pipe. It's not clear whether or not these cracks are actually leaking.
What's the best way to fix this?
As I see it, there are a number of choices:-
Presumably I could cut out the damaged area of pipe and repair the breaks using one of those flexible (rubber?) joints that are clamped to the pipe using stainless steel jubilee clips.
I'm a bit concerned about taking this approach because the joint between the clay and the cast-iron downpipe is above ground, so will be visible. The second concern is that, although this drain is close to the house, it's actually under a driveway, so technically could be driven over. Also, the drain is only about 150 mm below the surface. That sounds too shallow to be able to withstand the weight of a vehicle, even relatively infrequently.
I could also replace most of the pipe, but use a flexible joint so that I don't have to break into the benching in the manhole itself. If I go for replacement presumably I could use plastic or clay.
I could also replace the whole downpipe, but I don't really want to do that right now because it will affect the bathroom decor. I'd rather keep this as an 'outside only' job if I can.
So, given factors like a cast-iron downpipe (4.5 inch external diameter) and clay underground (approx 5.25 inch external diameter), the need for a connection between the cast iron and clay above ground, the shallow depth of soil cover, it's driveway location, etc, what's the best way to fix this?
Are there rigid fittings available that enable joints to be made between cast-iron and clay or plastic without having to resort to flexible connectors and jubilee clips?
Given the minimal depth of soil coverage, should I be protecting the pipe? If so, how's the best way to do it?
Any guidance and advice would be most welcome.
Thanks,
Mike
[Edit] I've just noticed that I've been promoted from 'apprentice' to 'digger'. Most appropriate, under the circumstances
