Cast iron drain pipe - replacement, odd size?

15 Jan 2018
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United Kingdom

We have an old house, 1860 era, a lot of the guttering /pipes are cast iron.

The upstairs sink waste is cast iron and runs on side of house from upstairs to outside drain. 2-3 meters in length...

The middle section has a crack end to end lengthways - split all the way through.

I have removed this section - 1.8 meter length section which top end seems to be 55mm internal diameter, 68mm external diameter (at the top socket end with ears)

The other end doesn't have a enlarged 'socket' or ears its just pipe this end the diameter of pipe is 55mm external diameter and approx. 45mm. internal... trying to work out what size pipe I need to buy to replace, is this a normal 68mm size pipe? i'm not sure what end/ internal /external diameter you refer to when purchasing?

I found some upvc cast iron style effect 1.8 meter pipe online which might fit, ideally id like to buy a new 1.8m section and just be able to slot it in, i'm mainly worried about the bottom end being the right size to fit inside the next section of cast iron pipe...

Any help would be greatly appreciated.... :D thanks in advance!
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ok thanks, so top end external 68mm pipe? (bottom end is 55mm external)
Sponsored Links there no definitive way a drain pipe is measured?
I can see pipes 68mm, 65mm, 110mm all the diagrams seem to show only the top... ...I found a couple with measurements for bottom but don't seem to be anywhere near 55mm
Top? those measurements are the pipe external diameter the top will be the same as bottom plus the collar of course
yes that makes sense, its confusing me due to excessive alcohol - and being a single one piece. :)

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