Condensation in corners of bedroom

johnbhoy70

Very interesting read for me as there are a lot of similarities to ourselves. We're in an 'older' new build so no cavity wall insulation here either and we're semi-detached with a bungalow. In a cold snap the windows are dripping in the morning and let's just say our Karcher window vac probably doesn't owe us anything. We need to go over about 4/5 with it and need to keep on top of it as we've wooden frames. Actually just noticed some dried in drips on the top of the wall above a window and radiator in our bedroom which i only painted in the summer. Same as you external walls the main culprit. Wasn't helped by the fact i'm almost sure the first time i cracked open the window trickle vents when we moved in was the first time they'd been opened. The loft is way more than adequately insulated. The only real main difference i can see is that this house is pretty warm and not very hard to heat to be honest. Even a wee blast from the CH in that recent cold spell and after about half an hour we're turning if off.

I've painted all the upstairs in the last few years and after a good wash with anti mould solution  hit it with anti mould paint before i started painting for real. Seems to be keeping it at bay for just now and it's not as bad as before. That's probably because we do most of what the guys have said on here.

Initially we bought a dehumidifer but can't remember when we last had it on. We have a tumble dryer in the garage and drying clothes is kept to an absolute minimum indoors. Told everyone even if they're home alone do not have a shower with bathroom door open and keep it closed after. When we remember in the morning we leave the upstairs windows open a touch. I'm aware these things haven't really resolved the problem but some of them appear to have kept it in check. 

Guy i used to work who was pretty handy told me to buy a corer for the walls and stick a couple of vents in??

_Sam_

People sometimes say you can learn to live with some condensation on windows - this is not the worry as such as I'd be happy to wipe the windows every other day or so if that was all. But the walls in unaccessible places is a bit of a concern - once a friend had to move her wardrobe in the bedroom and she discovered the entire wall behind it black with mould. And she'd been sleeping there and breathing it for years...

So every time there is condensation on windows I wonder where else could that condensation also be forming. We have few bookcases and some are against external walls, then the wardrobe, not possible to move these without half-dismantling them first! Dehumidifier may not be perfect in all regards but it does remove water from the air - after all it is there in the tray And with no condensation on windows, this gives some peace of mind that probably the walls are in good order too.

ThisIsWeird

johnbhoy70 said:

Very interesting read for me as there are a lot of similarities to ourselves. We're in an 'older' new build so no cavity wall insulation here either and we're semi-detached with a bungalow. In a cold snap the windows are dripping in the morning and let's just say our Karcher window vac probably doesn't owe us anything. We need to go over about 4/5 with it and need to keep on top of it as we've wooden frames. Actually just noticed some dried in drips on the top of the wall above a window and radiator in our bedroom which i only painted in the summer. Same as you external walls the main culprit. Wasn't helped by the fact i'm almost sure the first time i cracked open the window trickle vents when we moved in was the first time they'd been opened. The loft is way more than adequately insulated. The only real main difference i can see is that this house is pretty warm and not very hard to heat to be honest. Even a wee blast from the CH in that recent cold spell and after about half an hour we're turning if off.

I've painted all the upstairs in the last few years and after a good wash with anti mould solution  hit it with anti mould paint before i started painting for real. Seems to be keeping it at bay for just now and it's not as bad as before. That's probably because we do most of what the guys have said on here.

Initially we bought a dehumidifer but can't remember when we last had it on. We have a tumble dryer in the garage and drying clothes is kept to an absolute minimum indoors. Told everyone even if they're home alone do not have a shower with bathroom door open and keep it closed after. When we remember in the morning we leave the upstairs windows open a touch. I'm aware these things haven't really resolved the problem but some of them appear to have kept it in check. 

Guy i used to work who was pretty handy told me to buy a corer for the walls and stick a couple of vents in??

I repeat: Yes, I know it'll be bludy cold during the night if you open the windows to 'vent', but if you want to transform the condensation levels in your bedroom, that's exactly what you should be doing; you can easily keep warm by having an overnight leccy blanket running on '1' = very few watts if you need to.

First thing in t'morn, wipe away any remaining condensation, keep the heating off (ie on 'frost'), crack open the windows, shut the door and vent that room during the day and eve. Near bedtime, by all means you can close the windows and turn on the heating a half-to-one-hour (or whatevs) before bed so it's a pleasant greeting for you, but once you are ready to dive under the duvet, heating off and windows on 'vent' - more than one window if possible. Door always closed so you don't get the warm damp air from the rest of the house.

Have the heating set to come on a half-hour or whatevs before you get up, push partner out of bed to shut the windows and make a cuppa, and get up.

Once you leave the room, heating off, windows on vent, door shut. Repeat.

This will almost certainly transform the conditions in there.

Try this - prove it to yourself one way or another.

Scot_39

diego_94 said:

Have terrible condensation in main bedroom on the windows which I wipe off every morning, but what is concerning me more is that it is happening in the corner of the bedroom with some water running down the wall. Its started to go black, and has funnily enough got worse since we had new windows.

We are an Semi detached and the bedroom is on the outside corner, so 2 of the walls are external, these are extremely cold to touch especially in the cold weather we are having this week, and the cold weather we had before Christmas. There is no cavity wall insulation in the house, we looked to have it and were advised against it by the surveyor. As a result it is a cold house, and with the energy prices the way they are, we try to keep the heating off as much as possible. The bedroom gets down to about 12-13 degrees overnight

I open the windows every morning for 15 - 20 mins but it just gets wetter when I do this, I cant keep them on vent lock overnight as its so bloody cold and I'm not keeping the heating on all night. The windows don't have trickle vents. We do dry clothes inside, but this is in another bedroom (not no a radiator) and we keep the windows on vent when clothes are drying.

At a loss, what else can be tried? Thinking of a dehumidifier and maybe internal wall insulation? Any advice appreciated.

Another Vote here for Get a dehumidifier

Quick Fix at Best / Mitigation at Worst - Dehumidifier

They are a bit of a hot item right now it would seem.

But even a cheapish full size condensing dehumidifier will make a big difference to humidity in a heated house - even in a couple of hours of use a day.

It may solve the problem.

If not, should at least mitigate it - in terms of amount of condensation etc.

And cost should be offset a bit by I guess the non trivial cost of reheating spaces - after opening windows every morning for 15-20mins - especially right now when often 0C or lower outside.

Whilst you think about other options - re wall heat loss / long term energy costs

And/or look for other sources of water ingress as a potential reason (roof, guttering, walls - cracks in render, gaps in outer wall pointing etc - although would suspect walls a fair bit less likely without cavity insulation) for inner damp.

But it is sometimes really just condensation/ventillation vs a room temperature issue for mould.

Cost / Power Use

At c£150 - and 10L nominal capture capacity (ideal conditions) it was nearly the cheapest "full size" I could find (in local stores).

Found it good enough for my needs.

Larger home / larger household / damper home - may obviously need something bigger / better.  Remember it may only be showing up problematically in that one room - but other parts of the house may also have higher than ideal humidity.

Uses maybe 0.6-0.7kWh over 2 hrs on timer.

Thats far cheaper than re-heating the space after airing via open windows (for me that really means cooling 2 bedrooms and halls etc to get a proper through draft - so c70% of house) - on a cold day, and cheaper than using c10 yr old tumble dryer.

Certainly trivial compared to the 20-25kWh on heating daily in cold snap.

Even my 10l nominal capacity model can pull 1/2 pint - sometimes nearer a pint - from air in 2-3 hrs.

Not sure though how much of that would ever actually condense or soak onto/into surfaces (walls, carpets, soft furnishings etc) - rather than stay in air. 

But certainly says it's doing something (and my laundry does seem to dry a bit faster too).

If I didn't use it though - I know from past - the single glazed panels on my front door would be covered - even dripping condensation down wood panelling below on occassions.

Noise

My one is not the quietest of models in reviews by Which etc.

I have ran it in the bedroom - but if in a light sleep - sometimes "knew" when the compressor kicking in/out - even if didn't awaken me fully.

I now often run it just feet outside my bedroom door - for couple hours on cheap off-peak rate at night - doesn't keep me awake.

And to be honest don't often really feel the need to run in bedroom itself - as long as stay on top of general house humidity levels.

Cavity Insulation

I would take the surveyors advice.

A large % of UK homes are in areas where cavity wall insulation should generally - according to some at least - default to the assumption not advisable - until surveyed.

In part due to any increased risk of dampness in outer walls - wind exposure (driving rain onto walls) a big factor.

And then when it comes down to individual properties there can be issues with construction (design or bad practice) - that make it unadvisable even in a good weather risk area.

See section under damp problems if interested theres a map (and it might remind you of comments from surveyor)

https://www.which.co.uk/reviews/insulation/article/cavity-wall-insulation

As you say cavity looks out, and if find internal doesn't appeal - there are also external insulation panels - council / LHAs have fitted them on 1000s of houses near parents - rather than simply re-rendering/pebble dashing etc - come in different surfaces - and colours - cost ?

Windows

It wouldn't I guess normally be far from actual window if directly related to a leak etc - but then not a builder.

I would actually expect it at the window - based on past issue at parents house - if directly a leak or seal (or in their case a damaged render issue at side of window recess) the dampness was right next to and under new window etc.

The fact dampness was an issue before - might suggests may not be directly windows - apart from any reduction in ventillation aggrevating it. 

And any drop in heating / so room temperature - may also be enough of a trigger to make the mould risk worse.

And think not just ventillation in that bedroom - but rest of house (did you get a new tight sealed door - replacing drafty old one at the same time etc?).

Others here might be able to say more about rights or wrongs of a supplier fitting unvented windows in your case - in a room/house with past dampness issues.

Mould

If there is black mould - clean impacted surfaces with a bit of care - as best you can. It's not healthy in the long term - for you or any soft furnishings etc. to have mould spores around.

Read often - BBC and elsewhere - 14-15C min room temperature advised to avoid dampness issues turning to mould/spores etc.

A difficult target costwise these days for many.

If you have E7 - could you use a mini oil fired radiator or similar in that one bedroom - for a hour or two - to try keep it a bit warmer overnight if not whole house. 

Once you have mould - it will often spread unless "killed" (hot soapy water or bleach solution my approaches in past dependent on location ans risk to other furnishings) and the dampness source eradicated.

Painting over - similarly - only a temporary solution - if conditions remain as is.

I would hope a combination of a dehumidifier and less open window time so less reheat costs - allow an extra hour or so heat - at east in that bedrrom - to keep a higher average night temp - combined with the lower humidity - will prevent further mould returning if humidity only source.

Good luck solving it.

ashe

Just a quick question about these corner spots, will it not also be because it's a cold spot due to most houses not having insulation right up to the eaves to allow air circulation? As it's a corner on 2 external walls you'd expect if there is no insulation above both points then it would be naturally colder therefore a point for condensation to form?

Effician

Scot_39 said

And cost should be offset a bit by I guess the non trivial cost of reheating spaces - after opening windows every morning for 15-20mins - especially right now when often 0C or lower outside.

I'm guessing you have a sealed house with no ventilation & therefore no need to heat new incoming fresh air, doesn't sound particularly healthy.

ThisIsWeird

Scot_39 said:

Another Vote here for Get a dehumidifier

Quick Fix at Best / Mitigation at Worst - Dehumidifier

My 'method' requires no purchase, consumes no energy, produces no sound (unless you count external noise), can be put into place immediately, and is very likely to work.

Apart from that, your suggestion is better.

johnbhoy70

ThisIsWeird said:

johnbhoy70 said:

Very interesting read for me as there are a lot of similarities to ourselves. We're in an 'older' new build so no cavity wall insulation here either and we're semi-detached with a bungalow. In a cold snap the windows are dripping in the morning and let's just say our Karcher window vac probably doesn't owe us anything. We need to go over about 4/5 with it and need to keep on top of it as we've wooden frames. Actually just noticed some dried in drips on the top of the wall above a window and radiator in our bedroom which i only painted in the summer. Same as you external walls the main culprit. Wasn't helped by the fact i'm almost sure the first time i cracked open the window trickle vents when we moved in was the first time they'd been opened. The loft is way more than adequately insulated. The only real main difference i can see is that this house is pretty warm and not very hard to heat to be honest. Even a wee blast from the CH in that recent cold spell and after about half an hour we're turning if off.

I've painted all the upstairs in the last few years and after a good wash with anti mould solution  hit it with anti mould paint before i started painting for real. Seems to be keeping it at bay for just now and it's not as bad as before. That's probably because we do most of what the guys have said on here.

Initially we bought a dehumidifer but can't remember when we last had it on. We have a tumble dryer in the garage and drying clothes is kept to an absolute minimum indoors. Told everyone even if they're home alone do not have a shower with bathroom door open and keep it closed after. When we remember in the morning we leave the upstairs windows open a touch. I'm aware these things haven't really resolved the problem but some of them appear to have kept it in check. 

Guy i used to work who was pretty handy told me to buy a corer for the walls and stick a couple of vents in??

I repeat: Yes, I know it'll be bludy cold during the night if you open the windows to 'vent', but if you want to transform the condensation levels in your bedroom, that's exactly what you should be doing; you can easily keep warm by having an overnight leccy blanket running on '1' = very few watts if you need to.

First thing in t'morn, wipe away any remaining condensation, keep the heating off (ie on 'frost'), crack open the windows, shut the door and vent that room during the day and eve. Near bedtime, by all means you can close the windows and turn on the heating a half-to-one-hour (or whatevs) before bed so it's a pleasant greeting for you, but once you are ready to dive under the duvet, heating off and windows on 'vent' - more than one window if possible. Door always closed so you don't get the warm damp air from the rest of the house.

Have the heating set to come on a half-hour or whatevs before you get up, push partner out of bed to shut the windows and make a cuppa, and get up.

Once you leave the room, heating off, windows on vent, door shut. Repeat.

This will almost certainly transform the conditions in there.

Try this - prove it to yourself one way or another. 

and i repeat i already do/have done this with  a lot of the other measures and already proved it to myself. This includes leaving the relevant windows open a touch during the day whenever we remember and whenever possible. 

However, as i stated this is a very warm house but not warm enough that i'm leaving the windows open all night!! 

diego_94

Bit of an update here, we really made great effort over a few days to keep the windows open and doors closed upstairs, I then dried the corners out with a hairdryer. the windows get opened and door closed for 20 mins in the mornings

Also since I posted the bathroom door remains closed at all times with the windows on vent at all times. For about 20 mins following a shower the windows stay open, then back on vent.

Now the humidity is regularly between 50 and 60% most of the day upstairs and downstairs, and we only get a little bot of condensation on the windows if its really cold outside, but the corners of the room remain dry. I would much rather condensation on windows rather than the walls as at least I cen use a window vac on these and dry them off.

We plan to purchase a dehumidifier this year so we can use next winter.

thanks everyone for your help

johnbhoy70

diego_94 said:

Bit of an update here, we really made great effort over a few days to keep the windows open and doors closed upstairs, I then dried the corners out with a hairdryer. the windows get opened and door closed for 20 mins in the mornings

Also since I posted the bathroom door remains closed at all times with the windows on vent at all times. For about 20 mins following a shower the windows stay open, then back on vent.

Now the humidity is regularly between 50 and 60% most of the day upstairs and downstairs, and we only get a little bot of condensation on the windows if its really cold outside, but the corners of the room remain dry. I would much rather condensation on windows rather than the walls as at least I cen use a window vac on these and dry them off.

We plan to purchase a dehumidifier this year so we can use next winter.

thanks everyone for your help

It'll become habitual after a while. My kids will testify to that!!