Terrible condensation in bathroom

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Hi, each Winter in particular the ceiling in our bathroom gets terribly wet, dripping, and yet we've not had this at other houses we've owned.
Several years ago we fitted an extractor to try to limit it, but per the attached photo, it's still very bad.
It's really only the ceiling above the window, and above the bath.
What do people suggest to combat this, please? We are forced to clean it up, and then repaint each year.
1960s brick built, cavity wall, insulated loft, vented pitched roof, double-glazed, radiators.
TIA
Thanks
 

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Show us your extractor fan.

It seems to be ineffective.

When do you turn it on, and how long does it run for after your shower?

Go into the loft and check if the loft insulation fully covers the bathroom ceiling, or if it has been disturbed. How thick is it?
 
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Hi John, thanks for taking time to reply. The extractor was wired to the bathroom light, so is on and off with the light. My wife does have the bath very hot, and tends to switch light off as she leaves room. The extractor sits just under a meter from the damp patch, they apparently couldn't fit it closer due to the narrow pitch on the roof above making access difficult. It extracts to a vent within the soffet, i'll check whether any vapour leaves it tonight at bath time. The electrician who fitted the extractor said he'd used a decent powerful brand, but then he also said he'd fit an isolator switch, which he didn't. This was 5-6 years ago. Thanks
 

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it appears to be clogged with dust and fluff. Hoover and brush it clean. Have a look at the arrangement in the loft. You can probably fit a much more powerful one, assuming there is a bit of room above the ceiling and you have a 100mm duct. A typical builders fan has a throughput of about 60-80 cubic metres per hour, you can get one with 180 or 240 cu.m. The better ones have ball-bearing motors and are very quiet and economical in electricity use.

Try leaving the fan on longer, you should notice the window less steamy. If it is annoyingly noisy, that's another prompt to replace it.

You can have a new one wired with a run-on timer, up to half an hour, to dry the bathroom after use. This is quite easy if there is access to the wires in the ceiling rose, which from your description I expect there is.

Water vapour rises, so if the fan is in the ceiling, that will be OK.
 
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Thanks again, wasn't aware that that fluff could cause significant enough blockage, but will heed that advice :)

The room doesn't get steamy, just on the mirror, so i guess it's doing something right. ;)

I'll get in touch with my local sparky and ask him to have a look at it. I was never very impressed with the firm that fitted it ("building services"), so your opinion looks like matching the problem exactly :)

One more thought is wondering whether the amount of insulation above the ceiling differs from the edge by the wall to the rest of the room? Could that part of ceiling be significantly colder and therefore attract the damp moreso?

Thanks very much John.
 
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it's possible the insulation is gappy.

It's correct to draw it back from the eaves enough for air to pass to ventilate the loft and keep it dry, but that can be done by careful cutting with a big pair of wallpaper scissors.

here is an example of a better fan, with timer, from a good maker

https://www.tlc-direct.co.uk/Products/SLTD160T.html

As you see, it is too big to fix to the ceiling so it is mounted in the loft with ducting

even more powerful
https://www.tlc-direct.co.uk/Products/SLTD250T.html

They also do a "silent" range at a slightly higher price
 
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To be most effective the fan inlet should be directly above shower.
The fan should run every time the room is used not just with light.
 
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Three houses, mothers, our old, and our new, our old house problems, mothers and new house no problem, so looked at why, mothers house wet room so no shower door or curtain, new house shower door seals at bottom of shower, old house shower over bath so massive gap at bottom of shower, and that is seems is the problem, if the air can circulate through the shower cubical or area, then all the moisture is drawn into the room, but if there is no door or curtain, then the air and more to point moisture in the air does not circulate, so only shower gets wet not rest of room.

Clearly this spills over to any extractor position, above the shower it removes moist air before it enters room, anywhere else, it draws moist air into the room.

Shower doors that seal either top or bottom again stop circulation, a shower curtain clearly does not seal and air circulates, if you allow air to circulate then it will take longer to remove that damp air.

What @foxhole says is very true, with early building regulations it said the fan with a bathroom with a non opening window should have the ability to switch it on without the light, but this was dropped, fan on a PIR is better than fan on light as it works every time, however both mothers old house and this house we never use the fan and no problems with damp.

This house has old style central heating, the old C Plan, bathroom radiator and domestic hot water are thermo syphon or gravity, there is no TRV on the radiator and the towel rail radiator is working most of the time, so the room is always warm.

Any fan blowing air out of a room, can only work if air can also get into the room, cold air does not hold as much moisture as warm air, so if the replacement air comes from outside it will be drier than air from inside the house. Father-in-laws house was around 75% humidity because he had triple glazing and really well sealing doors, our old house same design, around 65% humidity, more air flow than his, and we cooked on electric not gas, mothers house more like 55% chimneys in house and doors with not thresh hold for wheel chair access did not seal as well, this house below 50% again chimney but open fire place, poor fitting loft lid.

If the house is humid then sucking in air from house will not help. Never seen humidity meter showing house so dry as here, at moment bedroom 47% temp 19.5°C and living room 43% temp 18.6°C. Weather high pressure at moment 1042 not normally that high. House size clearly also has a bearing on humidity, in general the smaller the house, the higher the humidity. I think our tumble drier with pipe through window in a unheated utility room must change the general humidity to other houses where we had a hole in the wall and tumble drier sucked in air heated by the central heating we have noticed the tumble drier in utility room does not need to run as long as in other house when sucking in centrally heated air.

It is no good looking at bathroom in isolation if the replacement air comes from rest of house. You show extractor, is there a vent in the door for air to be replaced? Or a gap under the bathroom door?
 
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Hi Eric, what a detailed reply thank you.
My wife prefers to have the bathroom as hot as possible, so leaving the window open a little is no option.i try to get her to close the bathroom door, but it doesn't help that our kids come and go leaving it adjar. The windows in the rooms closeby are usually misted as a result, as are the corners of those rooms... damp.
The rad in the bathroom does have a TRV and I have this set to medium, as the room is usually warm enough.
The pitch on the roof above is extremely shallow and I'm not sure the insulation reaches to the section of ceiling where the major damp occurs. Perhaps the ceiling here therefore is the coolest, furthest from rad too.
Bedroom next door is usually between 65 and 80 humidity, we have the window on vent mode and heating nice and warm.
I wonder whether to paint the ceiling with mould-resistant paint and also perhaps use one of those moisture absorbers on the window sill, although guess this will be full every other day.
 
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I can share the experience we had in our bathroom years ago... It only has a towel heater in there and on cold days the room filled with steam when showering, walls were dripping wet, mold in the corners at the bottom of the wall, etc. Our house is solid brick and the bathroom has two external walls.

1. I replaced the inadequate inline fan with a high rated (240) inline fan which helps get rid of most of the steam when showering.

2. I painted the walls with mould-resistant paint which looks the same as the paint there before. Regardless of what anybody says I have not had mold spores grow in the 3 years since painting it.

3. I created a gap at the bottom of the door of ½" which helps suck in more replacement air.

4. I had new loft insulation put in.

5. I turned the radiator up to maximum.

Regardless of outdoor temperature if the bathroom is warm (important) and the fan on with door shut (very important), there is very little condensation at all when showering. If the room isn't warm enough I get condensation on the walls but opening the window for an hour afterwards gets rid of it all.
 
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Great thanks, will get ceiling fan checked out, use mould-resistant paint, turn rad up to full, fit new lockable door (so that kids don't break in during hot bath time)
 
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Hi All.

My first post on here - and I thought best to follow on from this one, as it seems to answer some of my questions.

So I seem to have a similar problem, in that my bathroom just does not get rid of moisture after we have a shower. We keep the window closed, as I thought if it were to be open in cold times like this, it would make matters worse?

Anyway, I've taken some photos to show the general setup in the bathroom --- but from what I've read, it might be to do with the power of the fan? or something else? Here are the photos taken:


The fan is this one: https://www.toolstation.com/airvent-100mm-low-profile-extractor-fan/p26862

Thanks in advance for any further ideas that might help newbie me!
 
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Hi All.

My first post on here - and I thought best to follow on from this one, as it seems to answer some of my questions.

So I seem to have a similar problem, in that my bathroom just does not get rid of moisture after we have a shower. We keep the window closed, as I thought if it were to be open in cold times like this, it would make matters worse?

Anyway, I've taken some photos to show the general setup in the bathroom --- but from what I've read, it might be to do with the power of the fan? or something else? Here are the photos taken:


The fan is this one: https://www.toolstation.com/airvent-100mm-low-profile-extractor-fan/p26862

Thanks in advance for any further ideas that might help newbie me!
Fan is feeble, change for in-line fan in loft, plenty of room for it.


This type of thing.

https://www.screwfix.com/p/xpelair-...VVYBQBh0jtQKYEAQYBSABEgJvvPD_BwE&gclsrc=aw.ds
 
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Hi All.

My first post on here - and I thought best to follow on from this one, as it seems to answer some of my questions.

So I seem to have a similar problem, in that my bathroom just does not get rid of moisture after we have a shower. We keep the window closed, as I thought if it were to be open in cold times like this, it would make matters worse?
Better off starting a new thread tbh.

Anyway in our bathroom we don't have a working extractor fan (or at east I disconnected it), I just open the window wide when showering, there is no condensation issue at all. You absolutly should be opening the window. Mrs Mercury refuses to shower without the darn thing jammed shut so if I'm about I'll sneak in afterwards and open it wide, it's a constant battle tbh, much like wiping down the walls around the shower after every shower which Mrs Mercury and the sprogs will not even contemplate doing.
 
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Hi there, nothing worked until I bought Kair Anti-mould paint additive 50ml bottle. I've had two seasons now without mould regrowth and my ceiling actually drips with moisture. Our 60s house literally sweats, it's too well insulated.

Upgraded the fan to one which stays on for 15 mins after light goes off, made zero distance.

Cheers
 

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