condensation and damp

casa Miele Image
12/13/2010 - 05:29

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 its 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 rain fall this winter so far than they have had in a 100 years. With landslides and bridge closures e.t.c.  The builder said to me a year or more ago that 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 2 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????   HELP PLEASE  Many Thanks   Bianca



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 !! Good luck! S    

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.   Good Luck.

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 no cure teh problem. Ventilate well have a de-humidifier going, and try not to create to 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. Sorry can't do anything about the rain though...

Thank you for all the answers so far. I would hate to have to cover the stone up either inside or outside but maybe this is the answer. I will get a dehumidifier set up. Like Sprotsotoni we have double glazed windows and perhaps lack of ventilation. We have felt its a combination of all of the the things suggested  its just hard to know what to do.  I am glad at least that you have not all said, that's strange! Its nice to know its not just us.    Any ideas how to add ventilation that wont let all the heat out?    Thanks

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. If it helps I can let you know the name of the builder. Let's hope there won't be too much rain in the next few months!!!

"Just a few minutes twice a day, morning and evening should be enough. Switch off the heating while you ventilate." This won't work when the air in the house is damp from renovations etc. The best bet is get the house nice and warm and keep it so, and dehumidify for a long time Opening the windows and turning the heat off won't help at all   In the longer term, when the house has dried out properly, small solar powered ventilators [from boat builders] may help   []

We have a small bit of wall with this problem. As we have a fan kicking around I'm going to put it on a time switch and dry off the wall for half an hour each day.... worth a try. It's already got a spray of anti-mufa to keep the mould from getting hold.

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 breath.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 worst 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.That's our idea anyway_My husband is an italian builder and it's the only explaination we can think off. 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.

I fully agree with Maria and others who have commented so far. 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 had 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. S

There is a very good article on this topic which quotes some advice from the Spanish IDAE (Instituto para la Diversificación y Ahorro de la Energía). Unfortunately, it is in Spanish, but they recommend: 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, colour 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.

All the above advice holds water, as it were. 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.

"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 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 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...

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... The cost of that sort of excavation could be anything from 2-4 thousand Euro, plus the pipe. I think that would be prohibitive. Readings I am currently getting for ground loops @ 1.5 mtrs are circa 6C, albeit these are water based and on return recharge, so take a longer time to reheat.

to be honest i have not investigated actual costs of ground heat systems .. and i know badger always has figures to hand as it is his expertise...  my thought is not that it would be a viable heat solution...  but for someone with reasonable DIY skills a simple and effective way of going about not only adding air but also to keep a holiday home reasonably warm feeling .. to do this on the cheap yes you will need to have a friendly neighbor or builder that will dig trenches with a machine...  i understand most people will not know someone but for us if we asked for a trench of that nature to be dug it would be done for free in a day.. however to add in some reality to the equation say 200 euro to a mate .... is quite common for a days work for a mini digger.. the piping is exceedingly cheap too..  i would expect to get a system installed if i was attempting it.. for less than euro 500... and that would include some sort of solar to battery store system for supplying energy to the fans..   all i am saying is that most people buy property in detached locations..  and being Italy most people have slopes.. the other point is the sort of soil here does give benefit to this type of heat recovery...  so providing your place is not surrounded entirely by rock its a do-able to my mind project that requires very little capital with almost free benefits ... that if you are not going for full fledged alternative systems that will make it a useless exercise.. ie geothermal or photo voltaic.. in combination with traditional heating methods from pellets and wood to gas or electric.. this will be a cheap and easy installation to cut costs... there are many designs on the net and advise.. a few simple precautions are require to ensure moisture escapes..  and that the system will function to its best.. i prefer air systems as a choice  because its in answer to a question regarding damp elimination... also no leak problems ..its a much simpler idea with no skills required ...   the real point is that there is a vast pool of knowledge and alternatives to all problems and thinking outside the box can sometimes be useful..  when one looks for something simple and to my mind very cheap.... so i would debate very vigourously the estimate if you were to investigate, plan and install this system yourself.. i believe it would be hundreds of euros...  

I agree with Adriatica, lining the walls will temporarily hide the problem but you will soon see the damp and condensation coming through. This is what the previous owner of our watermill did in the downstairs cantina and we had to remove all the linings and allow the stone to breath. With proper ventilation, problem solved....

Sorry Adriatica. I was not recommending a Geo system, but only thinking mainly about the excavation cost for a few hundred metres of trenching at that sort of depth. I know with our type of excavation that it is normally around 2 days of digging/backfill for 200 mtrs using a large JCB.

In reply to by Badger

Badger... sorry too .. didnt mean to imply you were .. just acknowledging the fact that your price quotes are often more realistic than most .. and the mix up seems to come from me not making it clear this was a DIY type of suggestion not an alternative to a real heat source..  more a fix to the problems that so many face when they restore property here and seal of all air flow..  with an added warm air benefit..  you also have to realise that down here in darkest Abruzzo we have people that still work real days... and ripping a trench out of that nature in most areas will take them a half day..  and thats after a 4 hour lunch break.. you softeees in the marche obviously have harder ground or less muscle...

The guys I use are very fast and usually take only an hour for lunch. We are heavy clay based in this area,  so that could explain the difference. A heavily water based soil retains much more heat than a sand base, so for sand you have to excavate to a deeper level, but it is much faster.

Unfortunately if you want to live in a building that is sevral hundred years old, then you will have to trade of these problems which occur every Winter. Unless your house has been gutted and rebuilt to 'modern' standards then because of the method of construction of old solid walled houses (no cavity walls and little or no DPC) this will always be a problem. Most Italians I know accept this, as they are used to it, but as most Expats are used to houses with DPCs, full central heating and Air Bricks etc, this natural occurance of Condensation and rising damp will alway be in evidence. If you wish to avoid expensive and often ineffective treatments, I would suggest you look to new builds.

Flip we have lived here for ten years and have bought and restored three older properties and cannot agree about accepting problems because we have never had an ongoing and impossible problem with either damp or condensation... and i also have had many debates over the fact that new italian homes are any better, as they cannot have DPCS here it does not work with their tech specs and seismic regulations or land slip problems... so all property virtually is built with no rising damp protection as it does not allow the building to be fixed with no fracture in between sub soil and above soil ... in fact i would avoid a new Italian home as i feel much more secure with seeing a house that has stood a couple of hundred years or so and has not fallen down than many of the newer properties i see with gaping cracks and white mold lining the downstairs walls..  by using accepted and well thought out traditional materials you can avoid all problems providing the property is not situated on or against a major damp source.. into a wet hillside and or on a natural spring area... there are choices we all make but i would not write off traditional properties because of their age.. maybe because of their condition and position... basic elements regarding which way the house faces can make a world of difference and its location with the land surrounding it... these are the most important factors to my mind in either new or old builds ...       

adriatica Was not actually writing off 'Old' houses, we in fact live in a 600yr + house. What I meant that his type of remedial work should be carried out properly at the start of a renovation, as if it needs to be carried out retrospectively then costs are higher and often less effective. Personally I would rather live in a tent than a new build. What I was trying to allude to was peoples expectations in property condition in Italy should not be the same as elsewhere given Italys 'unique' circumstances.        

Remedial work is not less effective at all if done well but few people are prepared to put up with the mess necessary to fix the problem properly. They would rather go for the quick fix that will only last a year or two.

Flip.. this thread is full of my apologies.. i agree with your sentiments entirely...  re expectations .. and its a continuing and difficult area that i find myself in with people that will look at two properties and not be able to understand why one will cost pennies and others will have a normal market price.. people in their own back yards will understand price diferentials yet here a higher priced property is almost always atributed to ripping off foreigners..  there are excellent older properties and newer ones.. however if you choose say a new build off plan in Calabria on the coast dont be suprised if it follows the other previous apartment blocks into the sea or is just blown up because the mayor that owns the development company  suddenly realises its in a place where you are not allowed to build .. so saving any costs associated with making it habitable yet retaining deposits... however if you go fully into new builds here with reputable building firms and at realistic prices i have seen some wonderful homes... although not for me.. the same applies to older properties..  choose well ..investigate local prices.. above all have a list of immediate and essential requirements.. rule out all zone 1 sesimic areas.. should cut the choice a fair bit throughout Italy Wiki IT now gives the ratings on all comunes in its page so its very easy to investigate and not take an agents word.. why should you.. costs..  its going to cost a double fortune to make safe or restore a place bought in these areas and if it was safe it would be at a price you would not pay..  does that make sense .. not to me but it seems to me its how people look at places..  so expectations and lack of research and the belief in the dreaded "bargain" is what lets most people down .. there are no bargains here.. just lots of sharks        

What an interesting thread - thanks to everyone for putting forward such useful points. Our experience over the past 5 years in rennovating a 200 year old house is that once you solve one problem you find another one! Whatever you do don't be rushed into any quick fixes Because I am at heart a 'treehugger' I persuaded my partner to go along witth the idea of using just lime (putty and nhl 3.5) and sand to carry out the rennovations.Unfotnately when we've had to employ builders they have used some concrete but this has mainly been restricted to outside drains and the roof.I'm much hapier using lime as apart from when i flick it into my eyes (I now wear googles) its pleasent to work with. We cured a soaking wet room by digging out soil which was laying against the outside wall and putting in French drains to take water away -cost about 15 euros for the pipes.Inside we dug up all the floor(cement tiles laid onto stoney clay soil) until we got to a firm base which we compacted and added about 2ft of gravel to.This will have a compacted subfloor and bricks put on later this year. Most soil locally is clay which is notorious for staying very cold and wet if the heat/winds can't dry it out. By using clay or lime based plasters you will be allowing walls to breath but they are not easy for amateurs to use .If you leave a house shut up for periods of time you are likely to get all sorts of 'growths' and staining too.I've found lots of help and advice on the period property forum.

i think that many problems here are caused by casual approaches to how a building need to be restored and i admire the fact that someone is taking their own individual approach to how things should be done in their mind.. of course am about to add an "however" i think its limited to think that all problems can be resolved by reverting to older solutions there are many and varied and much cheaper solutions available using modern methods and i believe a carefully worked out project using both is maybe the best way and will obviously be lighter on your pocket if employing people as craftsmen and using reclaimed materials is often a lot more expensive... Abruzzo has a good example of restoration carried out to a very high degree of original or artisan labor in S. stefano in the province of L'Aquila .. a sort of place held up as a shining example of how places should be restored.. however two things to note here in my opinion... they used steel work throughout the restored buildings to ensure they manage to comply with seismic regulations in an area of class 1 risk...and then covered it all up with reclaimed or new hand made materials..  otherwise they would have just crumbled in the earthquake.. so behind the facade their is a very strong well designed system that pulls the whole place together.. which is the system generally used in most property but its cheaper to use enforced concrete so that the option most people go for.. then covering that up or filling in the skeleton with a more pleasing finish.. if a new build... however whatever is attempted here does need some sort of rigid and strong system behind it all to tie in roof.. intervening floors and foundations so that when the ground moves  the building does not kill you...    to my mind then its not possible to restore a building using traditional materials only in a class 1 seismic area in fact i would doubt anyone would be able to get a building certificated as habitable without proof that there was some sort of intervention within the restoration to ensure it did not shake to bits..  S Stefano is the proof that it can be done and it will look good and withstand major shocks.. but it comes at a very high cost... which when reading this forum you sort of get the idea that no-one is prepared for costs of normal restorations let alone one that will cost many times more.. a good idea might well be to look at the cost of a one bedroom small house in this remote village.. the cheapest there is in fact 198,000 euro.. from the look of it barely 40 m sq.. although they do not put a measurement so would say that i am giving it a generous margin.. which works out at 5000 euro a m sq when traditional property built to a safe standard in that area would be normally sold at less than 1000 euro a sq meter .. so it comes at a very high price.. this standard of work..   so whilst accepting the arguments that alternative solutions are available i do not accept that within class i or even 2 seismic zones they would provide you with a secure property to live in..  and that compacting floors by hand will be sufficient to secure a building that at some stage in its life is going to be shaken side to side like a dolls house by forces beyond most peoples comprehension without the normal concrete with steel mesh tying in the walls or metal bars through them.. or foundations packed hard against the foot of the wall tied around with steel to stop them slipping away... sorry i just do not accept that without a structural engineer advising on the interventions required that any of us can build a home or change structures securely unless we use at least a little bit of local awareness of buildings.. the local ratings of the area and the risks..  i know people like to use non italians and to complain over their work.. but i have seen many projects where the building has had all the major works carried out that ensure its safety .. put back together again to look like old and have no damp problems or safety issues using quick modern materials but also with the build not being constricted by a very low budget but a realistic one..  thats the problem i reckon for most of us.. is the illusion that work here can be carried out and produce a good result at a price below the norm.. it cannot but if people insist  the structural elements cannot be compromised but the filling in between those elements can be saved on..  for instance a floor at ground level if you have the funds and tell the builder can be raised with air gaps and never have a damp problem .. but it costs a lot more.. so budget wise.. a sheet of plastic concrete and steel is poured in... to keep the area safe but it will be humid.. so you paint the walls every yera and keep the windows open once a day.. but that what you want to pay for the they build it to a price... if you ask for the best way.. not the most economic.. and can explain what you want then you will get a home with no damp.. the opposite extreme of the S. Stefano place is the adverts for places at euro 25k-30k that used to be around..  they seem to have gone now..for restored properties with furniture at around the euro 500 a sq meter.. never seen one in real life so cannot comment from that point of view .. but the truth is that you cannot touch a property for much less than that as a builder.. well they will not so how can it be .. the price of the old original building plus restoration and furniture for less than you can employ a builder to do the work for...makes no sense .. yet people seemed to be lapping the idea up last year... and thats the real problem.. peoples expectations if you can give them what they expect then they just seem to blindly accept... a long way from damp problems.. but having read another thread about someone having difficulties and the comments on Italian builders i thought to tie it all up in one reply.. Italian builders are not all c*** or whatever someone called them.. lime render is not the solution to all ... a balanced approach.. a proper budget.. enough knowledge to ensure you can talk to a project manager and help in the design... and realistic expectations of costs, time and how involved you will have to be are all essential to achieve a good build in any place.. its very easy if done right..    


I have read that old houses need to breath .

The mortar to be used should not be sand and cement as this prevents breathability. 

Om Old buildings lime and sand was used.

This is breathable. 

If cement motor was used this changes the dynamics because no longer is there lime instead hard cement based motor which is impermeable 

You have to use a breathable mortar mix