Need to find a way to stop condensation on my bedroom window . It's causing black mold on window ledge walls

DJMK4

DJMK4

DJMK4

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Hi all.

I know how condensation occurs. And how it can cause black mold on surrounding surfaces..

I have abit of an issue which only seems present in my bedroom .I don't dry clothes in here. But the condensation mainly occurs overnight

I wake up in the morning and the inside of my window is covered in condensation , so I have to wipe it down open window slightly

It's got the point where black mold had developed on the window ledge ceiling bit. I will use white viniger and maybe abit of bleach to clear it down. However I need to do abit of plastering or filling around the window ledge soon and paint it with Dulux Matt paint again.

I want to do this but before I do I want to inspect the outside and maybe use a cartridge gun to reseal etc .

Before I look at maybe plastering or filling and painting. How do I cure this for good ? I don't want black mold to keep coming back

Thanks all
 
Your condensation will come from your breathing overnight. Do you share the room with anyone else overnight, such as a partner? It's said that a person exhales around half a pint of water vapour overnight so that it could be as much as a pint for two people sleeping eight hours.

Turn up the heating or set the window to trickle some air in.
 
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Nope it's just me. It happens a lot in the winter.

It doesn't happen in any other of my rooms..

Is there nothing (product or method) I could do to stop it ? I don't want to do some plastering., Painting etc if it's just going to keep coming back

I need to at some point replace this window. It leaks some draft in and there is plenty of road noise that leaks through it.

Is there any mold prevention product I can use before or after the plastering or repainting to help prevent it forming ?
 
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DJMK4 said:
Nope it's just me. It happens a lot in the winter.

It doesn't happen in any other of my rooms..

Is there nothing (product or method) I could do to stop it ? I don't want to do some plastering., Painting etc if it's just going to keep coming back

I need to at some point replace this window. It leaks some draft in and there is plenty of road noise that leaks through it.

Is there any mold prevention product I can use before or after the plastering or repainting to help prevent it forming ?
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Do you sleep in any of your other rooms though?
A dehumidifier running overnight might help a little if you don't mind/like the noise.
 
Do you keep your bedroom door open at night?


Maybe some of those silica gel pouches on the window sill? Or a dehumidifier? Will be a little noisy in a bedroom overnight though
 
DJMK4 said:
Nope it's just me. It happens a lot in the winter.

It doesn't happen in any other of my rooms..

Is there nothing (product or method) I could do to stop it ? I don't want to do some plastering., Painting etc if it's just going to keep coming back

I need to at some point replace this window. It leaks some draft in and there is plenty of road noise that leaks through it.

Is there any mold prevention product I can use before or after the plastering or repainting to help prevent it forming ?
Click to expand...
It will most likely be the water vapour while you breathe while sleeping. Our house (a converted bungalow with a main bedroom upstairs) suffers the same, and I sleep with my partner. I had to wipe the Veluxes this morning.
You could grab a dehumidifier; I recommend looking at this thread. Sleep with the door ajar and put the dehumidifier unit on the landing, hopefully drawing the water out of the bedroom.

Replacing a drafty window will worsen the issue, as you'll seal up any airflow, which will help regulate the humidity.

Seeing that other people's suggestions are the same, I'd go for both open doors and dehumidifiers.
 
Ok thanks all. I'll try some of those window pots for and packs first. Dehumidifiers are noisy but I'll try see what I can do

I'll try do a wipedown with just white viniger fist to get rid of it. I'll also ensure the window is wiped down every morning and I open the window when I wake up.

I'll go ahead as planned to do a plaster round the window and repaint

Most people in this street have been replacing the windows on their property with upgraded ones. So I can't see this being an issue in the long run
 
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I live in a modern house (2020) and get condensation on the bedroom windows in the rooms that are used overnight. It's just something that happens. I do have the trickle vents closed mind you... Might try them open tonight and see if it makes a difference
 
Ok I'll try trickle open too.. noise from local roads is the annoying thing for me

Iv been trying to work out If you can detach the trickle vents to clean. They have some screw caps on the inside of the window on the vents but i can't seem to get caps off or review any screws on the vents to unscrew and clean them.

I did try with one window and trying to get the caps off to reveal any screws almost broke the vents..

Not really a great product to find a way to get them off to clean them
 
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DJMK4 said:
Ok thanks all. I'll try some of those window pots for and packs first. Dehumidifiers are noisy but I'll try see what I can do

I'll try do a wipedown with just white viniger fist to get rid of it. I'll also ensure the window is wiped down every morning and I open the window when I wake up.

I'll go ahead as planned to do a plaster round the window and repaint

Most people in this street have been replacing the windows on their property with upgraded ones. So I can't see this being an issue in the long run
Click to expand...

We got a small one from the jungle that has whisper mode for overnight and is barely audible
 
When you say "window ledge ceiling", do you just mean the "ceiling" of the window alcove? Check this bit of ceiling isn't getting damp from something else, i.e. water ingress.

Cillit Bang is a good product for treating mould. I spray it on a kitchen sponge and then wipe it onto the surface, and then leave it, I don't rinse it off again. This inhibits the mould from growing back.

As you seem to be doing, keep the window as dry as possible. Use a microfibre cloth to wipe down the windows as regularly as possible, whenever you see water on the window preferably, and before going to bed if there is water on them. Then ring out the cloth if it's that wet, and leave it to dry in the best ventilated area of the house. You can also buy a Karcher window vac, which means you can pour away the water so you don't have cloths to dry.
 
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radderfire said:
When you say "window ledge ceiling", do you just mean the "ceiling" of the window alcove? Check this bit of ceiling isn't getting damp from something else, i.e. water ingress.

Cillit bang is a good product for treating mould. I spray it on a kitchen sponge and then wipe it onto the surface, and then leave it, I don't rinse it off again. This inhibits the mould from growing back.

As you seem to be doing, keep the window as dry as possible. Use a microfibre cloth to wipe down the windows as regularly as possible, whenever you see water on the window preferably, and before going to bed if there is water on them. Then ring out the cloth if it's that wet, and leave it to dry in the best ventilated area of the house. You can also buy a Karcher window vac, which means you can pour away the water so you don't have cloths to dry.
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I was thinking this.

Is it a cavity wall? If so water could be getting in the cavity from above due to a leaking roof, perished membrane, slipped tiles. As well if it's solid wall it could be that your gutters are broken and causing penetrating damp above your window. Could also be a leaking pipe in the loft if you have any pipework up there? Could be lots of causes.

If the primary issue was the condensation on windows from water vapour from breathing, I wouldn't expect mould on the roof of the window alcove to be the issue, usually at the bottom of the sides. To me it indicates water is getting in from above, which to me could be an issue I've just mentioned.
 
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Mason- said:
I was thinking this.

Is it a cavity wall? If so water could be getting in the cavity from above due to a leaking roof, perished membrane, slipped tiles. As well if it's solid wall it could be that your gutters are broken and causing penetrating damp above your window. Could also be a leaking pipe in the loft if you have any pipework up there? Could be lots of causes.

If the primary issue was the condensation on windows from water vapour from breathing, I wouldn't expect mould on the roof of the window alcove to be the issue, usually at the bottom of the sides. To me it indicates water is getting in from above, which to me could be an issue I've just mentioned.
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I will double check .there is a bathroom that would extracting through the loft then out the vent so I will check the extraction pipe and also replace it as it will do with a refresh probably. Although as it's only me it doenst get used much and I don't notice the condensation and mould on my bedroom window when I'm taking a shower. The extractor is always on.

. I will also redo the sealant on the outside of the house windows and any pvc ledges

When I mean window ledge ceiling I guess yes .as the window has its own surround or window reveal as they call it

I need to do a thin skim plaster around the window reveal inside , do I have to do anything before doing this as a protector ? Or is it just PVA and mix a small batch of plaster up and do a thin skim layer ?.. if I'm not plastering the rest of the room can use anglebead for the reveal edges and plaster the reveal and around the corner and blend it in to the inside walls which I'm not going to plaster.

What do people use on the edges between the inside wall and window ? Interior sealer ? Caulk or is there a plastic trimming that's supposed to separate the window frame and your wall?.
 
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Dehumidifier will help, as has been said.

For the black mold, wipe down with a white vinegar/water mix. A few goes of that if you have a dehumidifier going will clean it up and stop it coming back.

E: I should say I had this in my last house in the loft room. When winter hit the velux windows would be absolutely soaking by morning.

I found black mold on the frames and the wooden panel to the roof space that was behind shelves. The vinegar mix plus a dehumidifier sorted it out, didn't see it again.
 
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Anywhere you have humidity in the air (i.e. in a bedroom that you sleep in and breathe out water vapour), and a temperature differential (i.e. a window, or any surface that is cooler than the room ambient air) you'll end up with condensation.

If the condensation persists, eventually a spore will find it and black mold will start growing.

First you need to remove and kill the mold, then you need to keep the area dry.

In bedrooms, you can simply make sure you open the window every day.

Make sure you're not doing daft stuff like boiling water with no lid, running hot showers without a decent extraction system, drying clothes indoors without a dehumidifer etc.
 
DJMK4 said:
Hi all.

I know how condensation occurs. And how it can cause black mold on surrounding surfaces..

I have abit of an issue which only seems present in my bedroom .I don't dry clothes in here. But the condensation mainly occurs overnight

I wake up in the morning and the inside of my window is covered in condensation , so I have to wipe it down open window slightly

It's got the point where black mold had developed on the window ledge ceiling bit. I will use white viniger and maybe abit of bleach to clear it down. However I need to do abit of plastering or filling around the window ledge soon and paint it with Dulux Matt paint again.

I want to do this but before I do I want to inspect the outside and maybe use a cartridge gun to reseal etc .

Before I look at maybe plastering or filling and painting. How do I cure this for good ? I don't want black mold to keep coming back

Thanks all
Click to expand...

People breath out a lot of moisture overnight and it condenses on the cold window and surround. The only way is to turn the heating up or use a dehumidifier or open the window a bit. In this really cold weather, nothing much is going to stop it.
 
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