Hole in cast iron soil pipe

TheGreenFrog

There is a hole in the vertical section of an old cast iron soil pipe on the outside of my house.  The hole is about 2-3cms diameter (would need to get up a ladder to inspect more closely).  I think it has been there for quite some time and assume that it is caused by rust and is not a hole put there deliberately (can't think why it would be there on purpose).  I am intending to patch it but am not sure of the best product to use as there seem to be quite a few, from fibreglass wraps to metal clamps etc etc

jj_home_80

If the pipe is structurally sound apart from the hole, a repair wrap like Fernco or a fibreglass wrap should work well. For a longer-term fix, a metal repair clamp with a rubber seal would be more durable. If the pipe is badly corroded, though, it might be worth replacing that section to avoid future leaks.

ThisIsWeird

If you can confirm it ain't corrosion (if it is, then surely the rest of the pipe is junk?), then it can be easily filled with something like Stixall or a setting 'gutter sealant'.

Clean any loose debris from the exposed edge of the hole. Cut a thin card circle a cm or so larger than the hole. Stick a strongish thread through t'middle, knot it, and smear it with the Stixall. Partially curl it and pass it through, and use the thread to pull it snugly against the inside - hopefully enough Stixall on it for it to stick. Then, whilst still tugging gently on the thread, use a filling knife to fill the hole with more S-A, using the surrounding pipe surface as your guide. You should get it neat enough to barely be noticeable.

TheGreenFrog

ThisIsWeird said:

If you can confirm it ain't corrosion (if it is, then surely the rest of the pipe is junk?),

I will have to get up a ladder to look more closely but it doesn't look like it's caused by corrosion and the rest of the pipe seems sound.  Picture attached.

 

Grenage

If the paint is decent elsewhere on the run, it might just be localised corrosion. 

Another pipe might have gone in there at one point but it's probably the paint lifting and water getting in.

Veteransaver

Looks like it's just an old hole for an old pipe which presumably had a rubber bung/seal in it at some point that's now perished? Maybe just hammerite the rusted bit and then find a rubber seal to plug it up?

Section62

TheGreenFrog said:

ThisIsWeird said:

If you can confirm it ain't corrosion (if it is, then surely the rest of the pipe is junk?),

I will have to get up a ladder to look more closely but it doesn't look like it's caused by corrosion and the rest of the pipe seems sound.  Picture attached.

 

I'd probably put that down to hammer damage - either on purpose to create a hole for another pipe (e.g. an overflow) or accidentally when someone was trying to hit something else.

CI generally doesn't corrode that much - which is why it was/is a popular choice for soil pipe, guttering, manhole covers, gully grates, and all sorts of outdoor objects you see in gardens, in the street and on farms and transport (canals/railways) etc etc.

Not all cast irons are the same though, and it is possible your pipe had a defect from manufacture which has, over time, opened up to this hole.

born_again

MSE cheapskate method.
Cut a tin can to cover hole, bit of epoxy round hole & secure with a couple of jubilee clips 😶‍🌫️

Works well on exhaust pipes as well 🙋

twopenny

I used to use a resin filler that I had left over from car maintainance and have use the fibre glass patch that I also had pn my cast iron pipes. It was still there years later until I sold.

Touched up with multipurpose Bedec paint and that too did the trick saving a lot of hassle.

TheGreenFrog

I eventually got round to fixing this.  Tried a rubber bung as suggested by @Veteransaver, but hole was irregular size so did not work.  Eventual solution was to use a black adhesive/sealant to stick a piece of aluminium can over the hole and then smear the sealant over the aluminium to blend in.  Did not need a jubilee clip.  Thanks @born_again for the suggestion.