Causes of stains on walls

gifted

Apologies if this is in the wrong section. Can anyone tell me what is causing these stains on the walls? House is approximately 15 years old and is fairly ok insulation wise. These stains started appearing about 2 years ago in two of the bedrooms...always seem to be in the bathroom ( put that down to no vents in the bathroom)

Tom Hagen

Not enough ventilation in the bedrooms i'd guess..

MicktheMan

gifted wrote: »

Apologies if this is in the wrong section. Can anyone tell me what is causing these stains on the walls? House is approximately 15 years old and is fairly ok insulation wise. These stains started appearing about 2 years ago in two of the bedrooms...always seem to be in the bathroom ( put that down to no vents in the bathroom)

These "stains" as you call them are mould, a living organism which thrives anywhere there is excess moisture.

Would these rooms be on the North or East side of the house?

What "improvements" or changes were made 2 to 3 years ago (think stove install, heating change, insulation added etc)?

You have missing or disturbed insulation in the attic for starters, along with an imbalance in your heating and ventilation regime (sufficient heating & insufficient ventilation, insufficient heating & sufficient ventilation or insufficient heating & ventilation).

The more than likely cause in a nutshell is internally generated moisture being trapped in the house and condensing on cooler surfaces (in cooler rooms) allowing the mould to thrive.

Calahonda52

as above, OP take off the wall vent in the second pic and give us a look at the makeup pf the wall.
In the 3rd pic, take a pic of the corresponding spot out side
Thanks

BryanF

lack of heat/ appropriate ventilation X thermal bridging = mould

gifted

Hiya,

Thanks for replying, gave me a few things to think about.
I checked the insulation in the attic and it didn't seem to be sitting properly between the joists over the two bedrooms so I bought a roll of 200mm insulation and covered those areas again.

There's no permanent vent in bathroom and to be honest the window wouldn't be opened while showering, especially in the winter so I have to look at getting a fan fitted.

I've recently fitted a stove and have it connected to the heating system, I've only lit it a handful of times and even at that they were only small fires which meant the rads weren't really getting piping hot so that might have something to do with the lack of heat.

I've checked the space between the inside of the vent there's a 4" sewer pipe between both vents but I'm reckoning the outside vent is restricting the movement of air as the gaps are very small.

I've attached a pic of the outside of the bathroom window, it doesn't show much though.

Thanks again for your comments, a lot if food for thought there.

gifted

Hiya,

Thanks for replying, gave me a few things to think about.
I checked the insulation in the attic and it didn't seem to be sitting properly between the joists over the two bedrooms so I bought a roll of 200mm insulation and covered those areas again.

There's no permanent vent in bathroom and to be honest the window wouldn't be opened while showering, especially in the winter so I have to look at getting a fan fitted.

I've recently fitted a stove and have it connected to the heating system, I've only lit it a handful of times and even at that they were only small fires which meant the rads weren't really getting piping hot so that might have something to do with the lack of heat.

I've checked the space between the inside of the vent there's a 4" sewer pipe between both vents but I'm reckoning the outside vent is restricting the movement of air as the gaps are very small.

I've attached a pic of the outside of the bathroom window, it doesn't show much though.

Thanks again for your comments, a lot if food for thought there.

gifted

Pics attached hopefully

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Calahonda52

gifted wrote: »

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Thanks for the pics
ok, re the second picture, I can't see what is between the plaster board and the end of the circular wall vent.
It looks like the plasterboard is dabbed on, or maybe battens with some some insulation.

If it is the case that the air can get inside the plaster board, then thats a major problem and my guess is that this the case but you need to clarify this clearly for me please.

Its a very common construction problem.
Once you get back I will proposed a solution

punisher5112

Better ventilation as stated above also consider getting a dehumidifier as it will help especially in bedroom.

When sleeping and confined in a small room with lack of proper heat and ventilation it's will happen.

You can get electric plug in dehumidifier or the Aero 360 I believe it's called where it works offa block you put in and it attracts moisture and drains into base of container.

gifted

Calahonda52 wrote: »

Thanks for the pics
ok, re the second picture, I can't see what is between the plaster board and the end of the circular wall vent.
It looks like the plasterboard is dabbed on, or maybe battens with some some insulation.

If it is the case that the air can get inside the plaster board, then thats a major problem and my guess is that this the case but you need to clarify this clearly for me please.

Its a very common construction problem.
Once you get back I will proposed a solution

Hiya,
It's not plasterboard, just skim put onto the block wall.
Hope that helps.

Calahonda52

gifted wrote: »

Hiya,
It's not plasterboard, just skim put onto the block wall.
Hope that helps.

Thanks
Hollow block wall?

gifted

No, as far as I know it's a standard block on edge with aeroboard insulation between the blocks

Calahonda52

Okay, MMA footie over so lets go again.

The pipe is not properly sealed in the ope and there is cold air getting into the cavity and the aeroboard is not properly fitted over the window, hence the line in one of the first pictures.
Re the dehumidifier suggestion, wrong answer as the requirement is to get rid of the damp air pronto, the dehumidifier does not have the ability to deal with the increased moisture content in the air due to cooking, showering, breathing, drying clothes etc etc

gifted

Calahonda52 wrote: »

Okay, MMA footie over so lets go again.

The pipe is not properly sealed in the ope and there is cold air getting into the cavity and the aeroboard is not properly fitted over the window, hence the line in one of the first pictures.
Re the dehumidifier suggestion, wrong answer as the requirement is to get rid of the damp air pronto, the dehumidifier does not have the ability to deal with the increased moisture content in the air due to cooking, showering, breathing, drying clothes etc etc

That's the one with the pink curtains? Might pump that with expanding foam.

Thanks for taking the time to respond.

Calahonda52

gifted wrote: »

That's the one with the pink curtains? Might pump that with expanding foam.

Thanks for taking the time to respond.

No problem its always nice to tease it out with a OP who does what is suggested.
No foam, its not airtight! you need to tape from inside of pipe to outside of pb with airtight tape, it can be done with care and you wont see it behind the vent
I have a picture somewhere, have project managed c 50 houses in a 70 house estate with this problem, the owners got together and they helped each other out, I just examined each one before the vents went back
Pink room maybe but defo the other one, imo