Cold wall - condensation

stuart45

Looks like there's a good roof overhang to protect the wall. 
Once a wall gets damp it gets colder, which in turn attracts even more condensation. A VCL on the warm side of insulation helps stop trapping damp behind.

ThisIsWeird

moneysaver1978 said:

Yep! Blue/black are the coldest parts. There're no side panels so we are seeing an actual wall (with a bit of wallpaper!). I got the thermal camera as I wanted to make sure that the loft insulation is properly done and to make plans for early 2024 to address any cold spots.

The patch (on both ends) isn't that bad - although when we moved in, we did spot some mould which we treated with an anti-mould paint. When I run my hand through, it does feel like condensation (similar to what I see on the windows), hand is clean (none of these white chalk or bubbling) and it doesn't always happen. So unless I am mistaken, I don't think it is a penetrating leak coming from outside however, I am happy to be corrected!

Ah, I misread that 'step' in the wall - I thought it was a panel.

Ok, if that is the actual wall, then - yes - it'll be very cold, and the most prone to condensation forming on it - it's both cold, and has next to no ventilation over it. There's no real reason to suspect there's anything more than this going on.

What to do? I'd strip that paper off, and leave the cupboard door open so it hopefully dries out. I'd remove any softened plaster. Once dry, I'd coat that surface with SBR, and let that dry. Any actual signs of 'penetrating', then it might also be worth a coat of 'tanking', but I understand you'd need to get down to bare brick/stone/block for this.

Then I'd adhere a sheet of insulated plasterboard on top, and on the front return. 2" would be transformative, but even 1" should largely sort this.

Have a looksee out at that gutter, pipe and general area when it next tips down, and look for nasties.

moneysaver1978

stuart45 said:

Looks like there's a good roof overhang to protect the wall. 
Once a wall gets damp it gets colder, which in turn attracts even more condensation. A VCL on the warm side of insulation helps stop trapping damp behind.

A VCL works similar to https://www.wickes.co.uk/Kingspan-TW50-Thermal-Insulation-Board---1200-x-450-x-50mm/p/180440, right?

ThisIsWeird said:

Ah, I misread that 'step' in the wall - I thought it was a panel.

Ok, if that is the actual wall, then - yes - it'll be very cold, and the most prone to condensation forming on it - it's both cold, and has next to no ventilation over it. There's no real reason to suspect there's anything more than this going on.

What to do? I'd strip that paper off, and leave the cupboard door open so it hopefully dries out. I'd remove any softened plaster. Once dry, I'd coat that surface with SBR, and let that dry. Any actual signs of 'penetrating', then it might also be worth a coat of 'tanking', but I understand you'd need to get down to bare brick/stone/block for this.

Then I'd adhere a sheet of insulated plasterboard on top, and on the front return. 2" would be transformative, but even 1" should largely sort this.

Have a looksee out at that gutter, pipe and general area when it next tips down, and look for nasties.

Thankfully, the walls (inside and on surface of the wallpaper) are as dry as bone! The plaster isn't soft or crumbly which is I hope is a good sign.

Can you provide clarity on "adhere a sheet of insulated plasterboard on top, and on the front return"?

Also would putting an insulation board on the wall (and for a good measure, perhaps under the sloping ceiling) stop condensation from happening ever again? Would we still need to make holes to the doors?

stuart45

moneysaver1978 said:

stuart45 said:

Looks like there's a good roof overhang to protect the wall. 
Once a wall gets damp it gets colder, which in turn attracts even more condensation. A VCL on the warm side of insulation helps stop trapping damp behind.

A VCL works similar to https://www.wickes.co.uk/Kingspan-TW50-Thermal-Insulation-Board---1200-x-450-x-50mm/p/180440, right?

ThisIsWeird said:

Ah, I misread that 'step' in the wall - I thought it was a panel.

Ok, if that is the actual wall, then - yes - it'll be very cold, and the most prone to condensation forming on it - it's both cold, and has next to no ventilation over it. There's no real reason to suspect there's anything more than this going on.

What to do? I'd strip that paper off, and leave the cupboard door open so it hopefully dries out. I'd remove any softened plaster. Once dry, I'd coat that surface with SBR, and let that dry. Any actual signs of 'penetrating', then it might also be worth a coat of 'tanking', but I understand you'd need to get down to bare brick/stone/block for this.

Then I'd adhere a sheet of insulated plasterboard on top, and on the front return. 2" would be transformative, but even 1" should largely sort this.

Have a looksee out at that gutter, pipe and general area when it next tips down, and look for nasties.

Thankfully, the walls (inside and on surface of the wallpaper) are as dry as bone! The plaster isn't soft or crumbly which is I hope is a good sign.

Can you provide clarity on "adhere a sheet of insulated plasterboard on top, and on the front return"?

Also would putting an insulation board on the wall (and for a good measure, perhaps under the sloping ceiling) stop condensation from happening ever again? Would we still need to make holes to the doors?

Remember a VCL allows a small amount of moisture through, so if you tank the wall behind any moisture will condense on it and run down.
You need to tape the joints properly for the boards to work as a VCL.

ThisIsWeird

moneysaver1978 said:

ThisIsWeird said:

Ah, I misread that 'step' in the wall - I thought it was a panel.

Ok, if that is the actual wall, then - yes - it'll be very cold, and the most prone to condensation forming on it - it's both cold, and has next to no ventilation over it. There's no real reason to suspect there's anything more than this going on.

What to do? I'd strip that paper off, and leave the cupboard door open so it hopefully dries out. I'd remove any softened plaster. Once dry, I'd coat that surface with SBR, and let that dry. Any actual signs of 'penetrating', then it might also be worth a coat of 'tanking', but I understand you'd need to get down to bare brick/stone/block for this.

Then I'd adhere a sheet of insulated plasterboard on top, and on the front return. 2" would be transformative, but even 1" should largely sort this.

Have a looksee out at that gutter, pipe and general area when it next tips down, and look for nasties.

Thankfully, the walls (inside and on surface of the wallpaper) are as dry as bone! The plaster isn't soft or crumbly which is I hope is a good sign.

Can you provide clarity on "adhere a sheet of insulated plasterboard on top, and on the front return"?

Also would putting an insulation board on the wall (and for a good measure, perhaps under the sloping ceiling) stop condensation from happening ever again? Would we still need to make holes to the doors?

By 'front return' I meant to continue the insulated board around that raised front ridge so there's no cold exposed edge.

Ok, folk will have their opinions on this, but based on what you say - the plaster is dry, solid, and no signs of penetrating damp - I would simply dose the wall with SBR (after removing the wallpaper), brushing it on repeatedly until no more is absorbed, allow that to dry, and then adhere insulated p'board straight on. Lots of adhesive choices, one of my favs being Stixall. I would suggest that, almost certainly, that would solve the issue. Yes, possibly, penetrating damp might try and come through that wall and be trapped behind, but there's nothing to suggest it will. Worst case, the plaster layer will soften over time - many many years. And easy to sort. Best case - problem effectively solved.

Sloping ceilings are prone to have little - or zero - insulation above them due to difficult access and restricted space. So, adhering/screwing to the joists more insulated p'board over all your sloping ceiling will almost certainly return a significant insulation benefit. The flat parts of your ceilings - do you have normal 'loft' access to them? If so, normal loft insulation will be fine.

moneysaver1978

Thank you both!

It's been raining the last few hours and I am happy to report that the gutters are doing their job and the walls are dry (although cold as expected like the rest of the walls in the house!).

So like you said, it sounds like hot air from the room is escaping through the wardrobe reacting with the cold air and being inside the cupboards, not able to breath or condensate properly.

I did insulate the loft recently and all is good. The only areas I couldn't do are the sloping parts which sadly is a much bigger challenge.

So the plan in early 2024 is (correct me if I misunderstood!):

• remove wallpaper
• paint SBR on the wall - something like this.
• Add an insulation board with glue and tape with insulation aluminium foil tape 

Then we can look forward to at least warm clothes, no fear of condensation (wet clothes!) or worse case: mould forming!

The main thing I am unsure of is fitting the insulation boards inside the cupboard's fixtures:

• The railing fixed to the wall. Should the railing be on the insulation board or do I cut the insulation around to fit the railing (e.g. make a hole in the insulation)? If it's the former, I would need to cut the railing shorter.
• Same question for the shelf above the railing (you can see the support above the railing in the photo)
• The cupboard's front frames fixed to the wall.

moneysaver1978

Saw in a local Facebook group about cold wall and there were two mentions: Dryzone Anti-condensation paint and also a thermal liner.

Has anyone had used something like these before?

FreeBear

moneysaver1978 said:

Saw in a local Facebook group about cold wall and there were two mentions: Dryzone Anti-condensation paint and also a thermal liner.

Has anyone had used something like these before?

Thermal wallpaper/liner works for some people, but is not a long term solution. Any paint that claims magical insulating properties should be treated with a healthy dose of skepticism - The Dryzone stuff claims to contain hollow glass microspheres  that increases the surface temperature of the wall. Whilst that might be true, the difference will be imperceptible, and certainly not worth the money.

If you have a cold wall, the most cost effective solution is to insulate (either with PUR/PIR or cork/woodfibre) and put some heat in to the space.

moneysaver1978

FreeBear said:

moneysaver1978 said:

Saw in a local Facebook group about cold wall and there were two mentions: Dryzone Anti-condensation paint and also a thermal liner.

Has anyone had used something like these before?

Thermal wallpaper/liner works for some people, but is not a long term solution. Any paint that claims magical insulating properties should be treated with a healthy dose of skepticism - The Dryzone stuff claims to contain hollow glass microspheres  that increases the surface temperature of the wall. Whilst that might be true, the difference will be imperceptible, and certainly not worth the money.

If you have a cold wall, the most cost effective solution is to insulate (either with PUR/PIR or cork/woodfibre) and put some heat in to the space.

Thank you, I had the same feeling!

What are yours thoughts about fitting the PIRs around the cupboard fixings? Should everything be removed from the wall, and railings etc cut to size to fit the “new” wall?

FreeBear

moneysaver1978 said:

FreeBear said:

moneysaver1978 said:

Saw in a local Facebook group about cold wall and there were two mentions: Dryzone Anti-condensation paint and also a thermal liner.

Has anyone had used something like these before?

Thermal wallpaper/liner works for some people, but is not a long term solution. Any paint that claims magical insulating properties should be treated with a healthy dose of skepticism - The Dryzone stuff claims to contain hollow glass microspheres  that increases the surface temperature of the wall. Whilst that might be true, the difference will be imperceptible, and certainly not worth the money.

If you have a cold wall, the most cost effective solution is to insulate (either with PUR/PIR or cork/woodfibre) and put some heat in to the space.

Thank you, I had the same feeling!

What are yours thoughts about fitting the PIRs around the cupboard fixings? Should everything be removed from the wall, and railings etc cut to size to fit the “new” wall?

Not sure I follow what you are asking....

Currently insulating am external wall in a bedroom here. The wall has been stripped back to bare brick, and multiple layers of Kingspan stuck on. Aiming for 75mm of insulation which will exceed current requirements without losing much in the way of floor space.