Water Pipe Leaking In 2 Different Places Under Kitchen Floor?

When you reinstate that decking, I would create an easy-to-remove inspection panel which you can regularly lift out, check the drain and hose through with clean water. It's also good practice to occasionally fill the kitchen sink with clean, hot water and let it go, to flush waste pipework out - better than reaching for the dreaded 1-shot, sulphuric acid drain cleaner

Flush that drain out as soon as you can, maybe washing the hole in the wall too......fill both sides with sand / cement mix both sides - push it well in and leave it to set.
Stop whoever it is from flushing coffee grounds away.....strain and bin them.
Domestos is good for keeping drains wholesome!
John

dilalio said:

When you reinstate that decking, I would create an easy-to-remove inspection panel which you can regularly lift out, check the drain and hose through with clean water. It's also good practice to occasionally fill the kitchen sink with clean, hot water and let it go, to flush waste pipework out - better than reaching for the dreaded 1-shot, sulphuric acid drain cleaner

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The plumber advised exactly the same thing about the inspection panel, although I'm not sure exactly how I'm going to create it. I'll probably post this in the building forum too, I'm guessing maybe some sort of metallic wire meshing over it or maybe if I saw the decking at the drain point and possibly attach a handle to that saw off small piece of removable decking over the drain.

Thanks for tip about flushing out pipework. I had tried baking soda and vinegar but the amount of gunk and debris blocking the drain would have rendered it totally ineffective. Plumber said it was mainly cooking oil that was blocking it and he said it's unlikely the coffee had much to do with it.

Burnerman said:

Flush that drain out as soon as you can, maybe washing the hole in the wall too......fill both sides with sand / cement mix both sides - push it well in and leave it to set.
Stop whoever it is from flushing coffee grounds away.....strain and bin them.
Domestos is good for keeping drains wholesome!
John

Click to expand...

Thanks for the tips again John. The plumber said to use expanding foam in the hole, do you think that's a bad idea? I think the pipe in the drain is plastic rather than metal if that might effect the method of repair somehow?

Will bear in mind the tip about the coffee grounds, it's actually another housemate who's been doing that but also I've done it myself too in the past although these days I feed my bamboo plants with the coffee as they apparently like the nitrogen in the used grounds!

Expanding foam sure has its uses, but not here......it is affected by light (UV) and rodents and birds quite like it; its not waterproof enough in this situation either.
Use a sand and cement mix, and press it deep into the hole. The pipe material won't be affected either way.
Do the same on the other side, and replace the skirting that I advised you to remove !
Access to that outside drain needs to be simple, so think of how you can do that when you get a minute.
John