|How to get rid of Condensation on your Toilet Cistern!|
Plumbing Problems: HELP! I keep getting Condensation on my Toilet Cistern!
Solution: Insulate your Cistern!
We were having a problem with constantly getting condensation on the outside of the toilet cistern in our bathroom. This was a problem which we had had for a few years, and was especially worse in the winter as you would expect.
The cistern was attached on the inside of an external wall, and with the central heating usually on throughout the day, together with the fact that the toilet gets used/flushed a lot, so that the water inside rarely gets up to room temperature, we had a problem that was not just simply going to go away on its own!
Opening the windows and vents in the bathroom, was doing very little to help, because the pot wall of the toilet cistern was still so cold with it being attached to an external wall, and the low water temperature of the fresh water coming into the cistern was still causing the problem.
We had tried attaching a layer of foam to the wall behind the cistern, which did seem to help a little, but the ongoing condensation problem would usually cause this to get damp and it would usually rot a little, and require changing.
After searching the internet for a more permanent solution, it seemed that the answer was to bring hot water into the cistern or to lag the cistern internally.
Adding hot water seemed to me a little bit unhygienic, in that any mould or bacteria that develops would just be able to grow easier. Plus, the cost of constantly refilling of the toilet cistern with hot water would just be a waste of energy and would probably double the cost of the gas bill, and it really would just be a waste of energy resources.
So it seemed like the solution would be to insulate the cistern from the inside by lagging it. Those who had done this on the internet, seemed to have suggested using a yoga mat, and so whilst out shopping we soon found one that we thought would be ideal and made the purchase.
Although it seemed we were supposed to cut and glue a yoga mat to the inside of the cistern, it seemed that we could not obtain any definite answer on what glue we should be using! Some answers seemed to suggest a silicone sealant, but to me I had visions of the silicone peeling away with time under water and the lagging coming away within the cistern. Plus looking into the cistern seemed to suggest that a few large areas would have to be cut to allow for the parts to still fit & work correctly.
In the end I went back to my own original idea of using a tin of expanding foam to create a foam layer of whatever thickness I desired, we were not sure If I would be able to do this, but now we had a yoga mat, if all went wrong, we could clean off the expanding foam and try the yoga mat idea.
Expanding foam is probably the messiest stuff you can ever use, and if it gets on your hands it seems to stick forever and if it gets on your clothes it ruins them! For this reason I was going to use a supply of disposable gloves and change them as often as necessary, together with wearing a pair of overalls. I used elastic bands around the cuffs on the overalls to keep them from getting in the way, thus preventing expanding foam getting everywhere.
I had masked off the outside of the cistern to prevent it getting damaged, and had also masked off the area around the holes, knowing that due to the nature of expanding foam there was in fact little I could do to avoid getting foam where I did not want too, and this would help me achieve a better and cleaner finish where I needed it.
Now I was able to start the task, I would need to work on a section of the cistern at a time, starting at the base then going up each of the sides in turn.
Getting the expanding foam to stick to begin with was tricky, but covering an area with the foam and then trying to spread the foam with a plastic spreader, I did seem to have it mostly under control! (...but saying that I have a lot of patience, and for a task like this, you require patience more than anything!).
This was definitely not an easy task, and not one I would get perfectly right the first time, but armed with a long knife I would be able to trim and refill any areas as required until I could achieve the desired finish.
Using disposable gloves was definitely the right thing to do, luckily every time I needed to change 1 or both of them, I had someone on hand (get it!) to do this. (Trying to remove gloves that are covered in expanding foam by yourself is never a good idea!)
Once I had the whole of the inside of the toilet cistern covered in foam, and the foam had dried enough not to be sticky, I used the long sharp knife to slice the foam down to the required thickness. The foam on the base had to be the thinnest.
After fitting the flush unit and ball cock back into the cistern and refitting the cistern to the toilet/wall to test it, the cistern was not able to flush quite correctly, and we could see the problem was that the water could not exit fast enough into the flush unit when the toilet was flushed.
We took the cistern back off the wall, thinned out the foam under the flush unit and put it all back together and refitted it to the wall once more. Supertastic! It was now flushing as it should. We had lost a little of the flush force because of the foam in the cistern, but it was flushing with about 90% of the original force and we were more that happy with that.
Within a day it was immediately obvious we were no longer experiencing any condensation whatsoever, but this was summer, and we would just have to see what happens in the winter, which is when it used to be really bad. Well, when winter arrived, we not only got cold weather we got Manchester's coldest weather for 30 years, so this would be some test!
No problems whatsoever.
Now a year on it has made such a huge difference with not having to clean the condensation off the outside of the toilet cistern and without having to use drip trays on the floor underneath the cistern like we had had to in the past. What surprises me is that the foam has remained clean, I was not sure if it would end up getting moldy or rotten, but it's done nothing more that change to a slightly darker shade under the waterline. We have even gone to the trouble of tiling the bathroom floor now that the dripping water is no longer a problem. The old lino had been good at stopping water getting to the floorboards over the years, preventing any damage.
Using expanding foam was a cheap solution and it had worked and saved us having to purchase another cistern (perhaps a plastic one)(although we were never convinced that would of solved it anyway), and the only insulated boxes we had found on our travels were far too expensive to even consider.
If you are thinking of trying to do this with your own toilet cistern, I would say only attempt it if you are the sort of person who enjoys fixing problems like these, otherwise you will find this task to be a little bit on the impossible side!
This cistern would get covered in condensation on a daily basis. The condensation would run down the outside of the box from the level of the water downwards. The difference in temperature between the water / cistern and the room was too great to prevent the problem from continuing.
If we were to lag the cistern with a yoga mat, a large a area may have to be missed to allow the float to continue to move freely.
Fitting a yoga mat may also be a little difficult at this end too, & so we would try and use some expanding foam to see if we could work with that instead. If not we could always use the yoga mat.
The cistern was removed and cleaned. We even got out the pressure washer out, to make sure it got a thorough cleaning.
Then the outside of the cistern was covered in newspaper, to prevent any damage, and the holes were masked off.
Expanding foam was applied to the base,after this I applied expanding foam up the sides at either end.
After the base and ends had set enough so that they were not sticky to the touch (by which time they had expanded a little too!), I was then able to do 1 of the bigger sides.
As the cistern is narrow I allowed the first side to dry a little before attempting the opposite side.
Once the foam had expanded and begun to set I was able to begin cutting it back.
I used a long kitchen knife slicing the foam back to the required thickness.
Some areas were topped up with a little more foam as I went along.
Eventually things were being to look a little neater!
Trying to make sure the parts fit was going to require some parts of the foam insulation to be a little thinner than others. We had also bought a narrower float.
Everything fits. But when it was refitted to the toilet, it did not flush with much of a flow of water.
The cistern was taken back off the wall, the fittings were removed, and the foam on the base area of the cistern was thinned further.
We had put another piece of foam on the bathroom wall to try and prevent the cold wall temperature from having too much of a negative effect.
(This had only ever helped a little bit in the past because the main source of the cold temperature was still from the constant filling of the system with fresh cold water).
Everthings finally going back in place, hopefully we won't be needing the regular use of the sponge rag to wipe the box in future.
(seen here hiding behind the sink pipes/stand!)
Tested like this for a day or two, just to make sure we were happy with the way it filled & flushed.
We had even changed the handle for a nice shiny new one. (Having recently changed the taps from gold to silver coloured ones as well).
Finally, the condensation was a problem no more! After this we were finally able to tile the floor.