Cold water pipe condensation under kitchen sink

[KLye]

Hi all, after some practical experience from anyone who's experienced this. I have some fairly severe problems with the cold water pipe condensation under my sink dripping water all over the place. The house is new build (within the last 12 months) and faces onto the open Countryside so is fairly exposed to the elements (the kitchen is on this side as well).

So a few mistakes that have made the issue worse have been leaving too much cleaning crap under there preventing air flow - these have now been removed. Worse still is there's a water softener installed under there so aside from the extra piping, the system flushes through about 17 litres of cold water every few days when it cycles.

There's absolutely no lagging installed so I was considering buying some wrap around foam insulation stuff like THIS and seal every pipe - right after I clean up the mould.

So a few thoughts..

1. Do you consider it'll be sufficient to stop the problem?

2. This foam stuff is not going to be any good at insulating the flexible piping - is there another product you've used or can recommend?

3. I've considered blowing foam insulation behind the kitchen cabinets but I know this is bad for airflow - I still question whether it may be a better thing to do?

Let me know your thoughts!

Thanks.

 

[KLye]

Just to add.. I've been nosing through the wiki and past threads and couldn't find anything similar so excuse me if this has come up before!

 

[MJN]

Insulation should help by virtue of it reducing the opportunity for interfacing between the cold pipes and the surrounding air, however you should ought look at where all this damp air is coming from as in an otherwise 'dry' kitchen you should not be getting all that much condensation anyway.

Do you have an extractor fan/hood, and is it used?

Mathew

 

[KLye]

Cheers MJN.

It's definitely not damp. Purely condensation forming and running off the pipes. Where we live the water coming into the house is very very cold and being a new build is quite well insulated. Having a young infant at home, we generally keep the house warmer than normal (22 degrees) so despite having/using the appropriate vents and extractor fans the issue is still prevalent due to the temperature variance.

Any thoughts on additional insulation?

 

[leakydave]

Do you dry clothes on radiators, clothes horse etc? You need to try and reduce the water vapour from other sources, but don't stop breathing!

 

[JohnD]

put a plate under it. How much water per day? When did it start?

http://www.screwfix.com/p/pipe-insulation-15-x-25mm-1m/69211

 

[KLye]

Do you dry clothes on radiators, clothes horse etc? You need to try and reduce the water vapour from other sources, but don't stop breathing!

Hi Leakydave. Nope. We don't dry clothes on radiators that is but we do have clothes horses yes - although these are in a separate dining room where it's coolest.

Another point worth mentioning however is this is the location the main external pipe and stopcock.

I think I'll try and borrow a humidity reader and get some accurate readings on what the humidity is to be sure reducing it will have a big impact. Thanks for that.

Any other practical advise out there?

 

[KLye]

put a plate under it. How much water per day? When did it start?

http://www.screwfix.com/p/pipe-insulation-15-x-25mm-1m/69211[/QUOTE]
Hi John. It's always been the case since we took ownership. I've tried to challenge the Developers on it but they argue there's nothing in the NHBC regs that requires them to insulate the pipes. Furthermore because I had the softener installed (even though the issue existed before this) they use it as a means to slip responsibility.

What do you mean by plate? I confess I haven't taken an exact measurement - what will this tell you? I can't measure it if need be.

Yes, that is the insulation I was looking at but is it any good for flexible piping like this?

http://www.screwfix.com/p/jg-pflx15...x-bsp-300m-pack-of-2/72050?_requestid=1138367

 

[JohnD]

I meant a plate like you would eat your toast off. If there is a surprising amount it might be there is a leak dripping off the pipe. You can tie kitchen roll tightly round each end and the middle to check.

if not, there might be another leak under the sink or nearby causing excess humidity.

the 15mm insulation will fit a pipe of 15mm external diameter. Use tape to keep it tight. If the pipe and its fittings are too big, the next size up is 22mm insulation.

 

[MJN]

It's definitely not damp. Purely condensation forming and running off the pipes. Where we live the water coming into the house is very very cold and being a new build is quite well insulated.

Condensation does not occur merely due to temperature differentials - the air has to contain the water vapour in order to condense and whilst the incoming water may be cold it is no colder than anyone else's.

The dew point of air at 22C and 5C is however different and so some level of condensation is to be expected but the fact that yours is of a sufficient level to cause an issue suggests to me that you have too high a level of vapour in the air and so whilst insulation might help in this cupboard you may find you are merely pushing the problem elsewhere if you don't tackle the source.

Mathew

 

[KLye]

I meant a plate like you would eat your toast off. If there is a surprising amount it might be there is a leak dripping off the pipe. You can tie kitchen roll tightly round each end and the middle to check.

if not, there might be another leak under the sink or nearby causing excess humidity.

the 15mm insulation will fit a pipe of 15mm external diameter. Use tape to keep it tight. If the pipe and its fittings are too big, the next size up is 22mm insulation.

Cheers John. Bit tricky when the pipes are constantly wet anyway but I'll double check for leaks. Thanks for the tip on taping up the insulation - is there a specific tape I should be using?

Condensation does not occur merely due to temperature differentials - the air has to contain the water vapour in order to condense and whilst the incoming water may be cold it is no colder than anyone else's.

Well I'm not so sure about that. This isn't my first home - far from it and it's sure as heck a lot colder than elsewhere I've lived!

The dew point of air at 22C and 5C is however different and so some level of condensation is to be expected but the fact that yours is of a sufficient level to cause an issue suggests to me that you have too high a level of vapour in the air and so whilst insulation might help in this cupboard you may find you are merely pushing the problem elsewhere if you don't tackle the source.

That's really helpful. Thanks. So I'll really need to consider how to further reduce the humidity in addition to any insulation.

 

[KLye]

Ok. Some interesting additional observations from today. Turns out there's a heck of a lot of condensing going on on the exterior of the water softener. Air humidity aside.. as I'll attempt to do something about that as well, but can anyone recommend an effective method for insulating a water softener?

 

[Nige F]

Get some expanded polystyrene slabs from a diy store - make a box to fit over the unit . Stick the slabs together with decorators caulk and hold together with duct tape The lid can be left loose

 

[JohnD]

Air humidity aside..

No, not aside. It's the humidity that causes it. Run a hot shower and see if you get condensation on the window (you will).

 

[KLye]

No, not aside. It's the humidity that causes it. Run a hot shower and see if you get condensation on the window (you will).

You misinterpret what I write. I meant "aside" as in that part is already given and is something I'm going to address as mentioned above. I'll start by checking the extractor fans and making sure they're extracting warm moist air properly. I've also got a humidity meter on order so I can check actual humidity.

I'm also asking about additional things that can be done to help though.

Get some expanded polystyrene slabs from a diy store - make a box to fit over the unit . Stick the slabs together with decorators caulk and hold together with duct tape The lid can be left loose

Thanks Nige. Interesting idea although might be a bit of a squeeze you think given the small area (have a look below)?

I've just finished cleaning out the whole area so everything is clean and dry for the moment. Have raised the softener off the cabinet base with some supports to allow additional airflow.

Here's a snap of the area before I cleaned it up.

Under sink cabinet

• KLye
• 27 Feb 2012
• 1

condensation and mould area

I reckon a few other things I need to do is cut away some of that carcase base so it's not tight up against the pipe and shorten the softener pipes - I don't really understand why they were installed that long in the first place!