Water leak behind the wall
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- Captain Jack
- 3.0 24v
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- Location: Langford, Somerset
Water leak behind the wall
Since moving into our new house, we keep finding things that are wrong with it. It's a bit like buying a 2nd hand car! The one bit that is worrying me is the sound of a water leak behind the wall (or rather in that box thing).
Whenever a shower or water taps in the bathroom are on, there's a sound of water dripping on the floorboards. However, it's generally only when first turning on the water or a few seconds after. To me it sounds like a leak of a draining system, but there are a few other pipes going into the wall. My guess it's the PVC piping that's leaking. There are no visual signs of a water leak though. However, if the water did drip through the ceiling into the kitchen, it would drip into the same "box" downstairs.
I really don't feel like destroying the wall/box thing to get to the leak as we have just painted the room. Is there some kind of "Radweld" available for plugging minor(?) leaks in the drain system? Or should I get a plumber out and see what he says?
Whenever a shower or water taps in the bathroom are on, there's a sound of water dripping on the floorboards. However, it's generally only when first turning on the water or a few seconds after. To me it sounds like a leak of a draining system, but there are a few other pipes going into the wall. My guess it's the PVC piping that's leaking. There are no visual signs of a water leak though. However, if the water did drip through the ceiling into the kitchen, it would drip into the same "box" downstairs.
I really don't feel like destroying the wall/box thing to get to the leak as we have just painted the room. Is there some kind of "Radweld" available for plugging minor(?) leaks in the drain system? Or should I get a plumber out and see what he says?
2003 - 2008: 1998 Peugeot 406 2.1 TD 110bhp LX Saloon
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp
)
2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp

2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
- steve_earwig
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Re: Water leak behind the wall
"Oh yes sir, I'm going to have to completely demolish your house..."
I've never heard of a Rad Weld for drains, can you buy Rad Weld by the gallon? I guess this "box" has all the plumbing behind it, what's it made out of? What is the kitchen ceiling/bathroom floor made out of? If it is dripping then ignoring it might not be the best idea, it depends on the construction of course, but a slight drip for a few years could cause all sorts of damage that you won't know about 'til you take the express route from the bathroom to the kitchen.
And today's word is "endoscope".
I've never heard of a Rad Weld for drains, can you buy Rad Weld by the gallon? I guess this "box" has all the plumbing behind it, what's it made out of? What is the kitchen ceiling/bathroom floor made out of? If it is dripping then ignoring it might not be the best idea, it depends on the construction of course, but a slight drip for a few years could cause all sorts of damage that you won't know about 'til you take the express route from the bathroom to the kitchen.
And today's word is "endoscope".
Unskilled meddling sin©e 2007
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Re: Water leak behind the wall
My previous house came complete with a landlord that would hire the most useless plumber in the area. As a result I had water slowly dripping down the side of the house (exterior) for months. This caused substantial amounts of mould to grow in all 4 rooms that shared that wall (both bedrooms, living room and front room) and then it started shorting out the electric supply 
Get it fixed!!!
As for Rad-weld, it only works for short periods of time, and only because your coolant system is flooded with it. As soon as you change your coolant for some without rad-weld you'll be leaking worse than ever. As such it wouldn't be suitable for home use

Get it fixed!!!
As for Rad-weld, it only works for short periods of time, and only because your coolant system is flooded with it. As soon as you change your coolant for some without rad-weld you'll be leaking worse than ever. As such it wouldn't be suitable for home use
<steve_earwig> I think this forum is more about keeping our cars going with minimal outlay than giving our cars more reason to go bang
- Welly
- The moderator formally known as Welton
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Re: Water leak behind the wall
My house is relatively new (7 years) and the soil stack from the bathroom upstairs drops internally in a corner boxing to a 90 deg bend under the floor slab.....and away to drain.
The thing is they've installed the rising plastic stack (110mm diameter) on the piss, sorry, I mean not 'true and plumb'. The upshot is any small amounts of water going down pipe from a sink or whatever above tend to drop right down the centre of the pipe and 'splash' on the bend at the bottom causing a noise (think pissing into a toilet bowl). The water should almost cling to the inside wall of the pipe and be fairly quiet mostly.
If you can locate the manhole for the stack pipe then you can carry out a little test.......lift the manhole cover, fill the toilet with coloured food dye and flush it, watch the coloured water pass through the manhole and you pretty much confirm that the drain is functioning ok. If there was a genuine leak then expect the plasterwork at the base of the stack to be damp/crumbly.
Hope this helps.
The thing is they've installed the rising plastic stack (110mm diameter) on the piss, sorry, I mean not 'true and plumb'. The upshot is any small amounts of water going down pipe from a sink or whatever above tend to drop right down the centre of the pipe and 'splash' on the bend at the bottom causing a noise (think pissing into a toilet bowl). The water should almost cling to the inside wall of the pipe and be fairly quiet mostly.
If you can locate the manhole for the stack pipe then you can carry out a little test.......lift the manhole cover, fill the toilet with coloured food dye and flush it, watch the coloured water pass through the manhole and you pretty much confirm that the drain is functioning ok. If there was a genuine leak then expect the plasterwork at the base of the stack to be damp/crumbly.
Hope this helps.
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2021 Kia Spottage 1.6 Pez Turbo Dual Clutch Gearbox Trickery
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- DaiRees
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Re: Water leak behind the wall
Are you sure it's a leak CJ? Is it possible you could be hearing the plumbing expanding and contracting with different temperature of water running through it? I used to get a creak that could easily be mistaken for a drip in the ceiling caused by the central heating pipes expanding when the boiler fired up? Just a thought 

- Captain Jack
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Re: Water leak behind the wall
Yes, that's what my girlfriend is saying. She's saying it's too loud to be a dripping water noise.DaiRees wrote:Are you sure it's a leak CJ? Is it possible you could be hearing the plumbing expanding and contracting with different temperature of water running through it? I used to get a creak that could easily be mistaken for a drip in the ceiling caused by the central heating pipes expanding when the boiler fired up? Just a thought
Still, I'll get the plumber out and see what he says.
2003 - 2008: 1998 Peugeot 406 2.1 TD 110bhp LX Saloon
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp
)
2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp

2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
- Captain Jack
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- Joined: Sun Aug 07, 2005 11:26 am
- Location: Langford, Somerset
Re: Water leak behind the wall
Welp, Mr. Dynorod showed up yesterday (4 hours late) to have a look at the suspected leak. He said, it's probably the pipes contracting and expanding especially that there was no actual evidence of water anyway. Apparently, if that (loud) dripping noise was a leak, we'd be having a shower downstairs from the ceiling. He also checked the main drain pipe downstairs, into which the bath/sink ones go into, and it was bone dry. Not even condensation.
If it was his house, he would leave it alone, as it involves making a hole in the wall/box thing. The advantage of making a hole in the wall now is that we still have some paint left over from the room decoration, so would be relatively easy to patch up and match the paint...
If it was his house, he would leave it alone, as it involves making a hole in the wall/box thing. The advantage of making a hole in the wall now is that we still have some paint left over from the room decoration, so would be relatively easy to patch up and match the paint...
2003 - 2008: 1998 Peugeot 406 2.1 TD 110bhp LX Saloon
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp
)
2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp

2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
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- Site Admin & Mad Biker!
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Re: Water leak behind the wall
You sound as though you're convincing yourself that you want to take a look anyway Alex!
If it will give you piece of mind then cut a window in the plasterboard with a padsaw, save the bit you cut out! To make good stick a couple of bits of wood around the rear face of the plasterboard with no-nails so that you can stick the bit you removed back in. Bit of fine surface filler & jobs a good un!
If it will give you piece of mind then cut a window in the plasterboard with a padsaw, save the bit you cut out! To make good stick a couple of bits of wood around the rear face of the plasterboard with no-nails so that you can stick the bit you removed back in. Bit of fine surface filler & jobs a good un!
1996 406 1.8LX Got a bad case of hydro lock!
1996 406 Executive 2.0 Turbo XU10J2TE No longer hangin' on in there
1997 Honda CB500V
2003 Volvo V40 1.8 GDi SE killed by a nutter in a beemer 5 series
2008 Mondeo 2.0 TDCi Titanium X
"Always look on the bright side of life, dedo, dedo dedodedo"
1996 406 Executive 2.0 Turbo XU10J2TE No longer hangin' on in there

1997 Honda CB500V
2003 Volvo V40 1.8 GDi SE killed by a nutter in a beemer 5 series
2008 Mondeo 2.0 TDCi Titanium X
"Always look on the bright side of life, dedo, dedo dedodedo"
- Welly
- The moderator formally known as Welton
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Re: Water leak behind the wall
Teamy, we shall call you "billy bodger"
I still think it's the water dropping right down the centre of the pipe and splashing on the inside of the bend at the bottom.

I still think it's the water dropping right down the centre of the pipe and splashing on the inside of the bend at the bottom.
Cars in my care:
2021 Kia Spottage 1.6 Pez Turbo Dual Clutch Gearbox Trickery
2013 Renner Twingo - donkey work
2021 Kia Spottage 1.6 Pez Turbo Dual Clutch Gearbox Trickery
2013 Renner Twingo - donkey work
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- Site Admin & Mad Biker!
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Re: Water leak behind the wall
Welly wrote:Teamy, we shall call you "billy bodger"![]()

1996 406 1.8LX Got a bad case of hydro lock!
1996 406 Executive 2.0 Turbo XU10J2TE No longer hangin' on in there
1997 Honda CB500V
2003 Volvo V40 1.8 GDi SE killed by a nutter in a beemer 5 series
2008 Mondeo 2.0 TDCi Titanium X
"Always look on the bright side of life, dedo, dedo dedodedo"
1996 406 Executive 2.0 Turbo XU10J2TE No longer hangin' on in there

1997 Honda CB500V
2003 Volvo V40 1.8 GDi SE killed by a nutter in a beemer 5 series
2008 Mondeo 2.0 TDCi Titanium X
"Always look on the bright side of life, dedo, dedo dedodedo"