Condensation on cistern

Parents live in a small 1930's (or so) 1st floor flat with good double glazing, central heating etc. In the bathroom they get a huge amount of condensation on the cistern from water level downwards, particularly after having a bath/shower in the room. They resort to having a tray on the floor to catch the water as it drips off. It drives my mother loopy. They have had both plastic and porcelain(?) cisterns with the same problem. Any suggestions on what they can do to limit the condensation? What's different about their house that should cause it?

- dampness/high humidity/extra cold water supply?

Reply to
AA
Loading thread data ...

Lack of ventilation when taking a shower/bath.

Insufficient heating in the bathroom.

MBQ

Reply to
manatbandq

On 5 Dec 2006 04:59:30 -0800 someone who may be "AA" wrote this:-

1) They probably have the misfortune to have it fed from the mains. That means in winter it is a little colder then water from the cold tank would be and thus condensation is more likely. 2) They have inadequate heating/ventilation in the room. 3) It is possible to line the inside of the cistern with polystyrene, glued to the sides. This reduces the condensation a lot.
Reply to
David Hansen

I found the main cause of this was the old fashioned overflow pipe.

There is a fairly large open pipe going from the cistern out of the wall to the outside. Consequently the air in the top of the cistern is at outside temperature and this spreads to the water in the cistern and the casing.

Now I have a modern down the bog overflow, all condensation has vanished, no matter how often we flush the toilet with freezing water from the mains.

Reply to
EricP

The good double glazing is probably a mixed blessing. The drafty old windows that the place was probably built with would have provided for a fair bit of ventilation. Also I'd guess it was heated by open fires in the 1930s, which provide teriffic ventilation by drawing fresh air into the rooms and sending stale air up the chimney. Furthermore I would guess that the original inhabitants didn't go in much for nice steamy showers, which put huge amounts of water vapour into the air.

All-in-all, this leads to an microclimate with lots of moisture and nowhere much for it to go, especially in the bathroom. You really need to get an extractor fan in there. If you've already got one get a bigger one. I have a 150mm vent-axia one in my bathroom. If I turn it off before I take a shower everything gets steamed up. With the fan on the mirror stays perfectly clear. I've had the 100mm fans before in other bathrooms. Unless the room is not much bigger than a cupboard I don't find the smaller fans to be very effective.

Reply to
Martin Pentreath

A dip pipe, which takes the end of the overflow below the filled water level, is also effective at stopping cold air coming up it.

Colin Bignell

Reply to
nightjar

Thanks for all the suggestions. The room is well heated but they open the window a lot for ventilation especially during/after showering and have an extractor fan too. The dip pipe for the overflow and polystyrene lining are excellent ideas that i'll definitely try out.

Reply to
AA

On 6 Dec 2006 00:55:59 -0800 someone who may be "AA" wrote this:-

There is little point in running such a fan with the window open. They should use one or the other.

Reply to
David Hansen

During heating season thats a waste of money & energy. A humidistatic dehumidifier would work out cheaper.

NT

Reply to
meow2222

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.