100 yr old house, stone built with small cavity. In the cold weather damp appears to be drawn from outside and through the wall in the cold corner of the house (very exposed location and gets very cold in winter as cold air comes across the Yorkshire Dales).

So we have problems with mould and even actual water on the surface of some walls on the first floor – so it isn't rising damp.

So what is a solution? batons on the wall and insulated plasterboard?

I assume the warmer we have the house the more the problem will be evident as the cold moist air will leach onto the warm inner wall?

Anyone with any suggestions?

First thing is to bite the bullet and get a professional in to have a look.

whilst I admire the many words of wisdom that have contributed to the varied topics on which the STW massif have commented in the past, this is your house – its worth a shedload of money to you and you dont want to get amateur advice on a forum about bikes.

Thats not to say that there wont be a professional on here, but you cant decide anything till someone takes a look at it.

so it wasn't the builder's fault that you had damp around that window…

My semi-professional opinion is that the damp could be caused by moisture from inside the house, condensing in the cold corner. Most damp patches are caused by this, rather than moisture penetration probs.

The thermal resistance of the house structure in the corner may be lower than the rest of the wall, therefore forming a "cold bridge" which attracts moisture from inside the room.

Increased ventilation might help.

I sit next to someone in the office who might be able to offer a more informed opinion but he's not here very often.

If that wall is very cold it's possible it could be condensation. We had a similar problem inside the built in wardrobe in my son's bedroom. I lined the inside of that with the thin polystyrene you get on a roll and it's cured the problem.

You could insulate internally but then the solid wall won't benefit from the heat from inside the house which serves to keep it dry it out at some points in the year. This is especially true in a wind swept and wet exposed location.

They don't call solid wall properties "hard to treat" for nothing.

I'm currently having a small problem with a similar issue.

I recently had a new, more efficient boiler fitted and followed that up with new uPVC windows & doors. When the work was being done i found out that my gable end and rear wall (end terrace circa 1890) are double skinned with no cavity whatsoever, & the front wall only has a narrow cavity. Since the new stuff went in i've found condensation appearing on the (painted) wall in my front room and below my bedroom window. It's not much but with a combination of drying clothes in front of the radiators & breathing it's def. there.

Not too worried about it, might buy a dehumidifier to deal with the problem though.

Agree with Smudger – get the pro's in – should not cost or them to come look, quote…

In the meantime… given experience at our place – and advice from the pro's

on the 1st floor moisture will be coming down, not up….

How's the pointing? (Can't see it being this – whatever may come through would run down the inside of that external wall? – unless the cavity is blocked and making like a sponge…?)

Roof – had any work done on that?
If the roof tiles / lead flashing have gaps water can get up and under and, assuming your felt is fine, will run down the felt? – Lead flashing had cracked around our chimney – made a royal mess of the plaster in the attic bedroom….

Mould – we had it – have you furniture etc in front of the mouldy bits – a bit of damp in the walls and low air circulation = condensation which is what we had in a couple of spots, sounds like it could be the same for you?

Professional advice – We usedProfessional Remedial Services for the work at our place – I know they do travel far and wide so maybe worth a call….

Problems with mould and actual water on the surface of the walls sounds like
condensation.

The problem with professionals is they want to sell you their product! Are there truly independent people out there? I'd go with the general concensus that its condensation, specially as the wall appears to be wet on the surface.

Ventilate when cooking and showering, don't dry clothes in the house (or in that part of the house) open gas flames such as gas fires also create moisture I think.

I think one of the ways to prove condensation is to dry any surface water from the wall, and cover in a sheet of polythene, sealed all round with tape. If condensation, it will condense on the room side of the plastic, which is waterproof so can't be coming through the wall 🙂 If you give this a go, do a google and check the finer points to make sure its effective. Obviously when you do this, don't change any other behaviour such as drying clothes etc, as it would remove the possible cause and misslead you into thinking its not a condensation problem.

Bleedin' immigrants, they come over here, through our walls…

so it wasn't the builder's fault that you had damp around that window…

Well no it wouldn't be as he built a single storey extension and this is on the first floor. On the other side of the house.

Ohh, and the builder didn't construct a window that had damp seeping through, be constructed one that leaked.

😛

I have similar issues with my house (thick stone walls and damp), with my walls it is mostly condensation and the only real solution I've found is running a dehumidifier almost constantly through the colder months

We have a dehumidifier but also have two babies so there is always a huge amount of washing drying everywhere in the winter months.

We have just started sleeping with the blackout blind open (just thin curtains closed) as I thought that maybe we could encourage any condensation to form on the window. Doesn't seem to have helped yet (but early days on that theory).

in a couple of rooms the previous owners had 'papered' the walls with polystyrene insulation from a builders merchant, this was then cross lined with normal lining paper and this really made the walls a lot warmer to the touch with no noticeable condensation

On the whole the best way of dealing with condensation is to ventilate properly. Keep the kitchen and bathroom doors shut during and after use.
Do your drying somewhere that is ventilated well.
Open the windows on a regular basis to remove moisture in the air.

Keep the kitchen and bathroom doors shut during and after use.

Do that

Do your drying somewhere that is ventilated well.

We do it in the loft room and keep doors to the room closed as much as possible.

Open the windows on a regular basis to remove moisture in the air.

Try to do that but in the very cold weather we have to make sure the babies don't get too cold and also my wife has a huge phobia of spiders and sees the windows as a spider door unfortunately (we do open them quite regularly though).

if you're worried about drafts with small children get a dehumidifier – you need to make sure you can live witht he noise (like a small fridge) but will help with condensation issues.

We have one (see above) 🙂

It lives in the loft room – might get a new one though as it is on its last legs.

me? read the whole thread? you must be joking 😉