Has anyone got any advise regarding condensation? We have renovated and enlarged a stone property and are having some issues with the stones getting wet. Due to enlargement and having rendered much of the exterior stone there is only one wall that is stone on both the outside and the inside. This wall gets very wet when the room is used. It is fine when the house is left so it's not leaking but as soon as this room is heated in the winter the wall gets sodden, so much so that it has trickled down into plug sockets and has been causing the trip switch to go. We have disabled the plugs for now but obviously need a solution to the moisture. The wall has been re pointed inside and outside and our builder has renovated many stone houses before so he must have used the right stuff. It is the least-exposed wall of the property facing a forest so it is probably the last place to dry out when the sun does come out. The house, I should point out, is in the Lunigiana region of Tuscany that has had more rainfall this winter than usual, with landslides and bridge closures. The builder said to me a year or more ago that the house needs to learn to breathe and that this wetness will decrease over time but it does not seem to be, it is now much worse than before. Although this winter is the first year of full occupancy. So maybe he means two years of constant living? Has anyone else had this problem, and if so, how have you dealt with it? Should I be getting the wall re pointed? Can they paint the exterior stones with anything? I am getting a dehumidifier and have asked the people staying at the house to open windows a bit more, but other than this I am stumped.
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We have had similar problems and without any doubt at all, we feel strongly that it is due to lack of ventilation, the rooms that we have problems with are all double glazed (with no drainage facilities!!), and are therefore 'sealed'. Damp in the air has nowhere to go but to cling to the walls, thereby the walls get damp. A problem indeed !!
If the damp trouble occurs when you heat up the room - it sounds like warm moist air hitting a cold surface [the wall] and condensing on it To stop this happening you need to dry the air out - its probably a bit damp in the air from all the renovation works [cement and plaster drying out etc] and is apparent in the room as the wall lacks any plaster or render insulation - making it probably the coldest wall in the house. You could plaster it internally and/or render it externally. or you can open the windows as much as possible [great in winter!] to dry the whole house out [not just the problem room] Whatever you do, the problem should decrease as the house drys out - so you could just try living with it until the next summer when hopefully it will eventually dry out naturally De-humidifiers could help speed up the process, but whatever you do - get plenty of air circulating.
Like most old houses in Italy, the walls tend to be thick and therefore in winter, any moist air hitting a cold stone wall will cause condensation to form. You can treat the wall (PVA etc) but that will not solve the problem. Ventilate well, have a dehumidifier going, and try not to create too much steam (cooking/washing etc) in the area. It's a problem most of us suffer from, fortunately the winters are usually short until the warmer weather arrives.
We have a house in the Lunigiana area and have/had the same problem. One room was worse than the rest- we had water all along the floor enough to be able to dip my fingers in. We had a local builder in who hacked all the plaster and cement off in that room. He either coated the wall or mixed something in the new cement as it went on and when we were out November just gone the floor and walls were bone dry. Unfortunately we still had condensation running down the windows.
Building work brings literally hundreds of litres of water into the building and it's a good idea to have a dehumidifier to dry out the moisture when work has been completed and also frequently air the house. Make sure the new pointing has been done with "breathable materials." Certainly the cement used nowadays is almost completely chemical and will not allow the building to breathe. It is best to opt for "calce" to repoint any old building as it's what was used originally and it lets the moisture evaporate more. I think plastering inside or out would only make the problem worse as you would be adding more moisture and certainly not getting to the root of the problem. I agree with the advice about cooking. I think also that the houses in Britain probably have condensation but a lot of materials such as wood, wallpaper, carpets, etc, probably absorb it and disperse it slowly. My husband is an Italian builder and it's the only explanation we can think of. It seems to be a modern-day problem due to all the heating nowadays and hence resulting condensation, obviously the plastic-like building materials the trade uses doesn't help.
We had some tweaks done to a wall or two a year or so ago and when it was all finished we literally had water dripping down the walls. I actually thought that we must have had a pipe burst, but we had no pipes in the area. We left the windows slightly open for two days and miraculously it ALL disappeared. We still have some damp in certain rooms, but a minimal amount of ventilation works wonders.
1.- Ventilate by opening all windows for 10 minutes every day. 2.- Turn off heating at night. 3.- Switch on heating in the morning after ventilating the house. We have a stone watermill on the river, which is a 4 storey high with many different levels. The only place where we have had a few problems in the past was a cantina in the lower level where the previous owner had made some repairs which did not work. We removed all the false walls, left the natural stone to breathe and we combine ventilation and heating whenever we are there. It works!
We had a similar issue putting central heating and double glazing into old social housing stock. Condensation would run down the walls because suddenly there was no breath. Modern methods of construction are now using materials and systems from hundreds of years back. They're not only environmentally friendly, but they also have health benefits too. Earth plasters and finishes, made from clay or lime, are non toxic and allow walls to breathe, so that moisture trapped inside the walls can evaporate out. Don't seal a wall to address condensation. Clay, color pigmented paint is also available. Shove it on the wall and you never have to paint it. Couple this with a wind driven extraction fan with a heat exchanger. This creates pressure between the inside and outside air. Air is drawn in to the building from the outside and recovers the heat that would normally be lost to the outside by conduction. Moisture is also conducted out of the building and in this way both low humidity and temperature regulation is maintained inside the building. Its free from fossil fuel dependency as it runs on wind, effective and many asthma sufferers are finding this method of circulation actually eliminates their condition. If you have a chimney, it'd be a very simple solution. Retro fit isn't too tricky either. I've no idea about availability here in Italy, but its a widely used method in the UK and available.
I can appreciate the problems referred to, as I have had a old stone house in Lunigiana for many years. Its situation is made worse as the rear of the house is effectively a cliff face. We have found the only remedy when the house is unoccupied is to close all windows and shutters and to leave two dehumidifiers running, one on each floor. This does the trick, except when the bank forgets to pay the electricity bill! The dehumidifiers are not running continuously, as they switch off when the humidity is down to a reasonable level, and I do not think that the cost of running them is great.
We're currently in one of those wonderful apartments on Civitanova Marche's Lungomare. Essentially built for summer occupation only, they're built of 1960s concrete. In winter the warm, moist air resulting from breathing, moving, heating, cooking and washing things hits the cold, uncaring concrete of the outer walls and condenses in short order. The result is beastly muffa, or mould. With a swiff of something toxic it can be beaten back, but not for long. So now we open every window and door the second any hint of sunshine appears. Largely, this is helping. Were we here long-term however, I'd be thinking about lining the walls with something that didn't get so cold.
The normal solution would be to either line the walls with insulated plasterboard or construct a 'stud' wall against the existing walls Either method would usually involve using professionals and would knock up to about 100mm/wall off of the size of the room -and things like power points and switches will need moving. If its just a 'small' wall that is the problem, you could cover it with dense cork floor tiles [and make it a pin board!]
If you don't have a rising damp problem then the insulated plasterboard glued directly to the wall would work fine- provided you sealed all the gaps very well. The thinnest available gyproc board is around 30mm thick, with 20mm polystyrene. It comes in 3m by 1.2m sheets. Stick it directly onto the offending walls next summer. 1 big bag of adhesive should do 3 sheets of the insulated board. try googling gespol PE 13 pdf
lining walls will often only hide problems in my opinion and agree with most regarding the use odf traditional breathable products as the better solution .. however providing circulation will often make probes go away very quickly and i would suggest that a simple breathing block inserted into various rooms might well be a solution that is attempted before reaching a point of despair or a costly electrical bill... in fact by law here kitchens and bathrooms have to have some form of air exchange system even if only passive ..ie vents... and a house without will not be regarded as livable in law... and in truth if you have gas.. GPL without air circulation then its not only unhealthy but highly dangerous more so than mains gas as accumulations of this heavier than air gas accumulates at low levels and requires low level ventilation... anyway to add a further element to the debate.. and maybe another way of starting to keep temps up inside those with places that have sloping land could well benefit from adding a system that uses ground heat ..ie lay in a few hundred meters of pipe at aprox 2 meteres below ground and add a fan to draw the air in... and expel used air... the fan can be as small as a computer cooling fan... pipes need to slope away from house to let condensation roll downhill.. air sucked in will be at a pretty constant plus 12c .... not warm enough to live in but a much better starting base to add heat to than 0c... the other benefit is that in the summer its also a cooling system.. as 12c is a yearly constant... so not a suitable solution for all but its a cheap and sustainable simple heating cooling system that will air your house and pretty well eliminate all normal damp problems...whilst hopefully changing your fuel bills too and making a holiday home feel that little bit more comfortable when you arrive for a few days...