to ask why my flat would be more damp in the summer?

[Dieu]

Sorry, bit of a random one for AIBU, but I know that helpful and plentiful replies are more than likely on here.
I live in a basement flat in Edinburgh, so understand that there is going to be a bit of dampness. I bought a dehumidifier a few months ago and it has been great; it doesn't really solve the problem as such, but obviously helps with the excess moisture in the air.
In the winter, I was probably emptying the water collected once a week or so. However, now that it's summer, it needs emptying pretty much every day . So that's 2 litres of water every 1 - 2 days. The weather has admittedly been a bit muggy and we haven't needed the heating on (despite it still being fairly cool in the flat). However, there has been far less rain than normal.
The other slightly worrying thing is that our shower room ceiling has spots of black mould on. We ALWAYS run the extractor fan in there (nae windae) but today I put my hand at the vent on the outside wall and although you can hear the fan 'working', I could barely feel any air coming out of there at all. So it follows that the fan is woefully inadequate :( Does anyone know if this would be a big job to replace?
Excuse my ignorance folks, but single parenthood means that I now have to sort these things out myself, and we haven't been in the flat all that long.
Any advice or tips for dealing with damp would be much appreciated. Oh, and has anyone tried anti mould paint for bathrooms? Thanks.

We had the same thing with our bathroom ceiling in our old flat (had dehumidifier and cheap extractor fan too). Before painting you need to kill the mould and you can buy stuff to apply in b&q. I put it into a spray bottle sprayed the area and dabbed it in with a cloth (art ex ceiling meant it was harder to just wipe on). Once you kill off the mould paint over it with two coats of anti-damp paint and it does cover it and prevent it from coming back. I also left bathroom door open and hit a small non electric dehumidifier (the ones with crystals) and put it into the bathroom.

I am having exactly the same issue! Also a basement flat. I have had the dehumidifier on constantly. I wonder if it's because the heating isn't on and our flat is north facing so doesn't get super warm.

Have you had the windows open in this hot weather? The dehumidifier would be sucking the moist outdoor air too. It has been awfully humid this week, so I'd think that would explain that.

I think it's the higher humidity and no heating on.

We have a dehumidifier in ds1's small bedroom and it's doing a lot more work these last couple of months.

Warm air also holds more moisture than cold air so wet summer weather has higher humidity.

We live in a first floor flat (block of flats) and our bathroom smells like wet wood, roll on winter?

When we had the same it turned out that the header tank in the loft had a small leak. Worth checking we spent a small fortune in replacing the extractor and redecorating before we did

In winter your flat is warmer than outside temp (esp if you have heating on) therefore water in the air will condense less. In summer your flat is cooler than outside, so the water in the air will condense more. It's like how a very cold bottle of water will quickly get wet on the outside in hot weather.

Apologies if that's a too basic answer I'm not sure what you can do differently to change things.

My husband had put new fans in our bathrooms and it was easy. He is a mechanic though. I would try that, then treat the mold so you can properly vent out the fumes from the mold.
We used to use a dehumidifier when we lived somewhere else, and had to empty it daily during any humidity waves. Is it hot there, would an air conditioner help?

Is the flat one of those New Town 'Journey to the Centre of the Earth' jobs? I think that as the stone blocks get warmer more water is evaporating out of the building so you've got more in the air but less in the wood/plaster/whatnot.

I asked my husband and he said that there will be electrical wiring involved, it is easy if you are familar with, otherwise you could hire someone. It is about a 30-45 minute job. Be sure and buy a fan the same size as your existing fan, and also, you can get a more powerful one in the same size if you like. We did, technology improves. Until them I would suggest removing the fan cover and vacuming inside, that can help quite a bit sometime.
We painted the bathrooms with mildew resistant paint, and they remain mildew free. (We have no worries
In own in our bathrooms.) Hope that helps.

We had a ground floor flat till recently with a large cellar. It was always far damper in the summer - the floors would get damp patches, the walls would seep. Everything got a mouldy bloom on it and furniture glue melted away so things I had stored in there fell apart.

Also it stank in the summer.

I think it's because we didn't have the radiators on - there were radiators down there - and we had a recently fitted heating system. But the summer was always worse.

So helpful as ever, many thanks everyone.

windows in *our

Check for causes of damp- leaking roofs, blocked gutters, dodgy damp proofing, and causes of condensation- cooking without extractor on/ lids on pans, drying laundry, wet towels etc. Any dry day the sun shines turn the dehumidifier off and open the windows.