Blocked cast iron rainwater pipe

[Phil]

Got a job first thing in the morning to unblock this thing, if it wasn't a regular customer I wouldn't be bothered with it.

3 storey terraced house on a slope with cast iron down pipes every 5 or so houses, this one is blocked at the bottom according to the roofer.

Pipe goes straight into pavement with no access, what is the best way to unblock without replacing it all in plastic?

 

[Alanc]

cut in an inspection, then rod both directions

 

[Guest123]

If the pipe is blocked and water is backed up the lenghts of pipe, then it will be under pressure and you risk getting a soaking with stagnant water if you cut into it with a grinder! Stand to one side and drill a wee hole in the front of it and let the water out. Then make the hole wide enough to get spring rods down it. When it's cleared seal the small hole you've drilled with a small square of Flash Band or similar.

 

[Phil]

I've been meaning to get a set of spring rods, just don't asked to do this kind of work much. Last time I had this I managed to clear it in the end but it was hard work due to the compacted mud and stones.

Oh well, best see what I can do with some Speedfit pipe.

 

[LegionellaSlave]

Get the roofer to do it! :devilish:

 

[Guest123]

I've been meaning to get a set of spring rods, just don't asked to do this kind of work much. Last time I had this I managed to clear it in the end but it was hard work due to the compacted mud and stones.

Oh well, best see what I can do with some Speedfit pipe.

As a last resort, fit a small section of 15mm copper into a push fit straight and put this on the end of the Speedfit Pipe. Will give it some oomph at breaking up the blockage. For extra security, tape the whole thing up with duct tape, don't want to leave a push fit straight down there!

You could always hire a electric drain machine which is basically a long spring rod that revolves on the machine. They are really excellent and don't cost that much for a half day hire.