SOLVED. What's the likely cause (and fix) for this window mould please?

couriervanman

You are wasting your time taking all the trim off.......people have given the answer to the problem but you like your daughter aren't listening

Lack of ventilation
Not being cleaned regularly

ninjaef

couriervanman said:

You are wasting your time taking all the trim off.......people have given the answer to the problem but you like your daughter aren't listening

Lack of ventilation
Not being cleaned regularly

that will do now. thank you. please do not waste more of your time posting here. Thank you.

JIL

We had similar issues in our old house, the coldest rooms. The condensation hit the windows and mould would appear around the windows. It was always bad in winter, worse when there were five of us living in the house, 5 breathing people makes more water droplets, worse as the bathroom was upstairs and that added to the moisture.  We even resorted to using a bar towel on the window sills. I used the domestos spray bleach to clean it. 
We actually noticed a difference when one of the bedrooms was no longer in use and we were able to turn the radiator low and vent the windows.
From the pictures it does just look like surface mould. It's all at the bottom. Where water is able to collect.

ninjaef

JIL said:

We had similar issues in our old house, the coldest rooms. The condensation hit the windows and mould would appear around the windows. It was always bad in winter, worse when there were five of us living in the house, 5 breathing people makes more water droplets, worse as the bathroom was upstairs and that added to the moisture.  We even resorted to using a bar towel on the window sills. I used the domestos spray bleach to clean it. 
We actually noticed a difference when one of the bedrooms was no longer in use and we were able to turn the radiator low and vent the windows.
From the pictures it does just look like surface mould. It's all at the bottom. Where water is able to collect.

Very relevant. Thank you for this. yes, it is worse in Winter. I did ask her how long the window was installed. She said about 20yrs since she and hubby bought the house. He's a computer geek so completely useless around the home. Like me then. They do open the window mostly at weekend in the day when not occupied. The reason I talk about the trim and further inspection is that a builder friend came round yesterday and said check the window space fill and make sure that damp has not got into the substrate (walls) - just to check. There is most definitely a condensation problem - it is clear on the pics. And like many valued posts on here, there is most certainly something going on in there to cause the damp She no longer dries clothes on the rads - which is a NoNo for sure - but this is been going on for a long time and her cleaning with paper towels is not improving things.

Did domestos fix it - I heard bleach doesn't necessarily kill the spores?
Thanks for sharing the experience @JIL

Ah well, roll on tomorrow. 

fenwick458

couriervanman said:

You are wasting your time taking all the trim off.......people have given the answer to the problem but you like your daughter aren't listening

Lack of ventilation
Not being cleaned regularly

is there anyone other than me here who thinks that bit of black mould in silicone joints isn't a problem? I have it on the corner of some of my windows, it seems to be an absolute B****** to remove it, without actually removing the silicone/caulk. 
what's the alternative, clean it daily with bleach? I think I'd rather just leave it and forget about it

ninjaef

fenwick458 said:

couriervanman said:

You are wasting your time taking all the trim off.......people have given the answer to the problem but you like your daughter aren't listening

Lack of ventilation
Not being cleaned regularly

is there anyone other than me here who thinks that bit of black mould in silicone joints isn't a problem? I have it on the corner of some of my windows, it seems to be an absolute B****** to remove it, without actually removing the silicone/caulk. 
what's the alternative, clean it daily with bleach? I think I'd rather just leave it and forget about it

Yes, I am going to reseal with that "mould resistant" stuff from Screwfix. It is a PITA mould - I always am of the view that any problem in life requires that the root cause needs to be identified to determine the what solution will completely eradicate the problem. Although I have to concede that the strategy was less than effective where kids are concerned :-)

I've been scouring the net today, about this black mould, and read conflicting information about bleach being effective. Even Tea Tree Oil was recommended - not sure how that kills mould - but I am no expert all , hence why I came here.

Jeepers_Creepers

Son's bedroom has similar condensation along the bottoms of the glass panes and up their edges most mornings. He has the windows firmly shut at night, and that's what he wakes up to. There is one exception to the continuous line of pooled water; in one bottom corner of one pane, the black rubber glazing-unit seal has a teeny gap in it where the corner mitres don't quite touch - and there is a bone dry channel rising up on the glass as if someone had wiped it dry with their finger. The teeny tiny trickle of air coming through that teeny tiny gap keeps that one corner bone dry. The rest is sopping.

When he complained that things he'd left on the sill - I think it was books - were damp in the morning, I told him to crack open both windows to 'vent' setting last thing at night and to jump into bed. He did this a for a few nights, and for these few nights there was NO condensation on his glass in the mornings. He won't keep doing it, tho', as he finds it chilly... However, what he does now do is fling both windows wide open as soon as he gets up and leaves his bedroom for breakfast - in around an hour all traces of the water has gone. 

Mil's connie suffered from very wet windows in winter like those in your photos, except worse. They didn't use the room in cold weather, but did access their garden through it all the time, so the DG doors from the house were opened regularly into it, and this obviously allowed a flow of warm moist air to get in there each time. "Why are the windows wet?" she asked. "Because it's cold in there" I replied. "How can we fix it?" "By leaving a couple of windows on opposite sides cracked open to vent setting all the time." "Won't that make the room colder still?!" "Yes. But it'll also vent it dry..."  And it did. It was colder - but bone dry.

And now for some truisms...

1) The window in your photo has not been cleaned for - oooh - a month. If it was cleaned less than a month ago - and I doubt very much it has - it wasn't cleaned properly. For black mould to build up in that sort of thick layer requires the surface to have been kept damp repeatedly for a good few weeks; that mould is having a party.

2) Cleaning that window is peasy. Cif and a toothbrush. Wipe it clean & dry. Spray on Astonish M&MB. Leave it for an hour or more. Jobbie jobbed.

3) What you have on these windows is perfectly normal under the circumstances. It is not a 'fault'. It is due to the bedroom being cooler overnight than it is in the evening - so the warm, moist-laden evening air cools overnight and can no longer hold that water suspended in it. It therefore finds the coldest surface to release the water onto - and that is the glass.

4) This could largely be sorted by keeping the room temp high all night so the water remains in air-suspension, but the water in the air won't have 'disappeared' and will still be looking for the next-cooler surfaces to condense out on instead. Once the air becomes saturated, it will no longer hold additional water - eg from sleeping bodies - so even this 'solution' will fail at some point, unless you keep raising and raising the temp... When you now open the bedroom door in the morning, the searingly-hot water-saturated air will flow out - and find somewhere else in the house to condense onto instead. So that plan is crazy.

5) The other way to sort it is to ventilate the room. If you can, have the windows cracked open during the night. If you cannot, then simply wipe away all the water first thing in the morning, and then leave the windows cracked open to vent for an hour. How hard is that?

6) Stick a dehumidifier in there if you like. Yes, that will help, but unless you run it through the night you will very likely still have some condensation on the glass in the morning. But why have a whirring machine when a cracked-open window will do it naturally, quietly and at no cost?

7) I like writing. It's fun. But often frustrating.

ccluedo

Reading this thread am I correct in thinking that for rooms that are infrequently used then no matter the outside weather/ temperature - even if in the minuses - the recommendation would be no heat/low heat, door closed and window slightly open? Would trickle vent open suffice instead of window?

neilmcl

ninjaef said:

fenwick458 said:

couriervanman said:

You are wasting your time taking all the trim off.......people have given the answer to the problem but you like your daughter aren't listening

Lack of ventilation
Not being cleaned regularly

is there anyone other than me here who thinks that bit of black mould in silicone joints isn't a problem? I have it on the corner of some of my windows, it seems to be an absolute B****** to remove it, without actually removing the silicone/caulk. 
what's the alternative, clean it daily with bleach? I think I'd rather just leave it and forget about it

Yes, I am going to reseal with that "mould resistant" stuff from Screwfix. It is a PITA mould - I always am of the view that any problem in life requires that the root cause needs to be identified to determine the what solution will completely eradicate the problem. Although I have to concede that the strategy was less than effective where kids are concerned :-)

I've been scouring the net today, about this black mould, and read conflicting information about bleach being effective. Even Tea Tree Oil was recommended - not sure how that kills mould - but I am no expert all , hence why I came here.

I believe we've all advised what the root problem is, and it's a simple, common one that's easily rectified, or at least kept on top off.

I'm sorry to have to say this but you do seem to like posting a lot of threads on this forum seeking advice, thanking everyone who have taken the time to give such advice, then totally ignoring the advice given. For this reason I will no longer respond. I wish you luck.

Jeepers_Creepers

ccluedo said:

Reading this thread am I correct in thinking that for rooms that are infrequently used then no matter the outside weather/ temperature - even if in the minuses - the recommendation would be no heat/low heat, door closed and window slightly open? Would trickle vent open suffice instead of window?

Yes and no :-)   

As I understand it, in theory, yes - that's all you need to do to a room that isn't being used - keep it well ventilated.

In practice, it might not be good to allow it to become too cold because - even with the door shut - some warm moist air from the rest of the house will find its way in there, around the door-to-frame gaps, and literally through walls. Any part of the room that isn't being ventilated well - eg behind pulled-back curtains, low down in room corners, behind units and inside wardrobes etc - could still suffer from condensation issues over time from this. It wouldn't be good to allow the room to become almost freezing as even the smallest amount of moist air will find a surface to condense on to.  The colder it is, the more ventilating it'll need, so 'trickle' might not be enough if it's freezing outside.

It's what I would do as a starting point; any room that wasn't needed for a month or more and you really didn't want to use energy heating it like the rest of the house, I'd shut the door and leave the windows on 'vent'. Trickle vents should also be enough, but it would make sense to monitor the room on a weekly basis - check it feels fresh. If the outside temp drops to well below, I might change that arrangement and set the rad to 1-2 so as not to have too great a contrast with the rest of the house - give it some 'background' warmth as well. And you won't get much through-ventilating from a single window, or two trickle vents side-by-side.