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    • CommentAuthorludite
    • CommentTimeMay 12th 2008
    Hi Friends,

    We have a small 70's 2 bedroom bungalow which we inherited. We replaced the old upvc windows with new (still upvc), we had a solid wood floor placed cross ways over the original floor boards and we did matching skirting boards (we sealed the gaps between the two with silicon). We rendered over the front of the bungalow It was originally half wood clad and half an odd assortment of brick. We replaced the roof - the felt and all the soffits) We swapped the oil fired central heating for a gas combi boiler, and we had a daylight sun tube put in the living room.

    We then lived in it for 2 years.

    We rented the bungalow out and the lodgers have continuously complained about mildew and condensation. When I went round to view the property last winter, it was in both bedrooms, the hallway and against the coldest wall of the living room.

    I supplied a dehumidifier, suggested they stop drying their clothes on the radiators, maybe ran the central heating a little longer (they did it two hours a night) and opened their windows (as far as the security cracks allow).

    I had a professional come round and check the property and he assurred them - and us - that there was no damp in the building, and the property was sound. He said there was no need to put added ventilation fans in the bathroom - the lodgers had wanted to bash a hole through our new render - and he suggested opening the windows to ventilate the property.

    I checked the air bricks, I even had a hole cut in our brand new floor to show them there was no damp below the building - then I committed the cardinal sin, and entered the property when they were out - but they knew I was coming over - and saw they were using the dehumidifier as a bedside table - not turned on, all the windows were sealed shut, and there were soaking wet clothes on the cold radiators.

    I need to know more about condensation:

    Will it damage our bungalow in the long term?
    Can I get rid of it?
    Could there be a problem with the fabric of our building - or the alterations we carried out? The 'expert' just said we'd created a thermally efficient house with no draughts.

    I want our lodgers to live in comfort and I don't want our house to rot away, what can I do?

    Thanks for any help and suggestions.

    I've had this problem many times with tenants and have it also with the rental property that I am renting at the moment. The secret it is find out what the necessary balance of ventilation and heating is. Have your windows got trickle vents? If so open them all. Failing that, I'd make sure that a small opening light in the window in each room is locked in the "vent" position at all times. Have you got a room thermostat to control the heating? If the house is maintained at a more constant temperature there will be less condensation. Bleach off all the existing mould. Humidity controlled fans in the bathroom and kitchen would help. There will not be a problem in the summer in any case.
    • CommentAuthorStuartB
    • CommentTimeMay 12th 2008
    Give them a months notice and find new tenants who will look after your property.
    • CommentAuthorchipedwood
    • CommentTimeMay 12th 2008
    I have a huge problem with condensation damp and mildew in my flat.

    It only occors in one room of the flat. The bathroom is fully tiled so no damp in there but the bedroom i very cold 2/4 external walls and a concrete floor. Also there is not insulation in this room.

    As far as I know the reason is because the room is cold so water is condensing against the wall and causing damp in the darker areas. I have a dehumidifier that runs 5 hours a day and have heating on for about 4-6 hours a day.

    I even fitted a mechanical vent in the bathroom that I run constantly. Soon I am going to invest in a dryer to avoid drying clothes on the radiators.

    All this aside, the point I am trying to make is once damp gets onto the walls it is VERY hard to get rid of. I will have to redecorate the bedroom once I completely get rid of this damp.

    Condensation does not cause a huge amount of damange in this instance the worst case would be damage to the plaster or skirtings if they are not treated well.

    The trick with condensation is to ensure the walls are not cold and there is adquate ventilation in place. The work you carried out could of caused it as you may have had unwanted ventilation but it was keeping the condensation down.
    • CommentAuthorludite
    • CommentTimeMay 12th 2008
    Thanks for your comments so far. When I was first called out to the problem I told the lodgers that the reason the mould did not occur in the bathroom, was because it only had one small external wall. It was collecting in the cold spots of their bedroom because that was the coldest part of the house.

    I was really torn by their complaints, because my husbands grandmother had lived there for many years with no problems, and we had lived there with no problems - although having said that, I was at home 24/7 with looking after kids, so the heating was on and we were always in and out - so fanning humid air out of the house.

    What really frustrates me, is that they have been told of the cause of the condensation/mould, they have been provided with a dehumidifier. . . .and they still won't open the windows!!! when the subject of cleaning the walls with bleach (or mould remover) came up - they said they didn't like the fumes. . . . .

    I was just wondering if there was ANYTHING I might have overlooked. . . . . I discussed the possibility of putting in vents with the expert, and he pointed out that if they weren't opening the windows, they would probably block the vents if they were installed. . . . And my husband refused because we had already cut a hole in the floor to prove there wasn't a problem and he wasn't about to start hacking at his house on a whim.
    • CommentAuthortony
    • CommentTimeMay 12th 2008
    Whole "house" mechanical heat recover ventilation would solve the problem so long as it was not switched off.

    Also drying washing indoors and complaining about condensation should be against the law.
    • CommentAuthorchuckey
    • CommentTimeMay 12th 2008
    Even as you sleep you sweat out a couple of pints of water. Very often if the bedhead is against an external wall, when the bed is moved the wallpaper will have mould on it.
    The most likely spots for condensation is firstly on window frames and then inside built in cupboards. As you window frames are plastic, not much of a problem here. The other places are de-facto suffering from low air flow (no heat!) and hence low transfer of water vapour, so, yes there could be a problem but it might take a couple of decades to materialise.
    • CommentAuthorcaliwag
    • CommentTimeMay 12th 2008
    Sadly tenants rarely look after a place as if it were their own...bit like lending tools and books!
    Drying clothes on rads is THE sin...You just have to lay down the law or they're out, and leave instruction sheets for the next lot. I advise a management company on maintenance issues. Now these are mid 80s conversions with "heritage" single glazed sash windows (air leaky or what?) and some tenants still manage to complain about condensation and consequent mould damage on window ledges and in areas with limited circulation. This is only going to get worse as fuel prices run away.

    BRE, or whatever they are called now, use to produce a cracking little leaflet on the basics...remember it's heating, insulation, ventilation and you cannot take one away!! That's all the tenant needs to know...they of course resent such advise, blaming the landlord or construction...government program?...we only vote the bu**ers in to look after us
    • CommentAuthorludite
    • CommentTimeMay 12th 2008
    I am starting to feel slightly more confident that I have done as much as I can do to explain the situation to the lodgers. As I say, the agents who got us the lodgers employed an 'expert' to give his opinion, because even the agent was surprised at the amount of mould and condensation in the house. . . . . he unfortunately told the lodgers of his surprise and they became convinced that there was a problem.

    I reminded the agent that he was the one who had personally come round and viewed the property when we were living in it - 2 adults, 2 kids, a parrot and a cat - and he had neither felt, nor seen any signs of mould or humidity, so why should he say to the lodgers that he thought there might be a problem?

    As I say, could I have forgotten anything? On this website I hear so many people go on about insulation, and airtightness, how can you insulate and make it air tight and NOT have a problem with humidity?

    Incidentially, Tony, mechanical heat recovery was only suggested to me once before - and that was by a firm who makes the machines. I was recommended them by RENTOKIL, as they don't deal with mildew. It would certainly be something I might install in a house I was living in, but I was a bit reluctant to do it in rented, as it seems that the first solution would be to open the windows and/or use the dehumidifier, and as they weren't doing either, it seemed like a bit of a waste of money.
    I anguished over this problem for a long time in our house, used dehumidifiers, opened windows as much as I could etc etc. I then found and investigated posotive ventilation systems. Again much anguish and £950 later a 95% reduction in condensation, also came wtih a money back guarantee. Couple of companies that do them, i went with envirovent as they use recycled materials for the unit bodies and install their own product.

    Helpful tidy installers, no I dont work for them its just rare for me to be happy with the jobs tradespeople do!

    Bonus being much cheaper to run than the dehumidifiers.
    • CommentTimeMay 12th 2008
    I had a positive flow ventilation system

    It was great - my hubby has very bad asthma & that balck mould was a nightmare

    But after a couple of weeks of it being switched on (when I scrubbed it all off with bleach) it never came back

    Mine was about £500 - not recycled - but my dad wondered if a bathroom fan fitted backwards would work (which if it worked would be cheaper)
    • CommentAuthorcaliwag
    • CommentTimeMay 12th 2008
    Out of curiosity, how do the parrot and the cat get on?
    We took on a 6 year old yellow sulphur...with no provenance...nightmare, contolled the house with it's loud, instructional squawks. When it escaped once, it assumed the vaccuum cable was a snake and chomped the entire length, which might account for its wild behaviour. Anyway became a very expensive donation to Flamingo land who can do nothing with him either...looks imperious though.

    Seriously, you don't need to consider dehumidifiers etc., just get the occupants to live properly...perhaps the local authority have a brochure on how to live in a house...Jeez!
    • CommentAuthorludite
    • CommentTimeMay 13th 2008
    Although it's not strictly green building, I have to answer caliwag. Parrot is a male Jardines and we've had him around 9 years. He was very tame, but as he matured he became very aggressively unpredictable - used to fly off perch and once bit husband hard in face when he was in the bath. When we started having kids we stopped letting him out of his cage (and once kids started walking, we raised the perspex portion of the cage surround) - but he is still very much part of the family (idolises my sister but would still bite her given the chance) - we now have 2 cats, both strays who just turned up and stayed - (and 2 guinea pigs who sort of arrived too) all of them get on fine. Perspex now lowered and kids know not to touch the cage.

    Our long term goal is to build our bird a large outdoor avairy and get him a girlfriend (have all the materials ready, just nowhere to put it yet) - as most mornings he makes love, long and slow to a bell in his cage. (the problem with parrots is that once they mature they do tend to get a little aggressive, which is when people give them away, we were prepared that once we had kids, and the bird grew up, he might not be an ideal pet, however, he is part of our family and as they live a long time, we thought it was best if he just put up with his present single status until we can get him a mate, rather than give him away) Regarding flexes, I think parrots are scared of them, ours certainly is.

    Regarding noise. . . . . I think, on the whole, we are a very noisy family - no asbos yet though - when we start shouting/screaming/singing etc, the bird joins in, and to tell you the truth, we don't notice it - but I think our previous neighbours did!

    I think my dream home would be a combination of the eden project and a sea life centre, to live in a big 'green house' surrounded by plants and animals all running around is my idea of heaven. Have just fallen in love with the work of mexican architect Javier Senosiain - type his name in google and see what you think.:bigsmile:
    • CommentAuthorcaliwag
    • CommentTimeMay 13th 2008
    Ha Ha...ours did the same...anyway, not a parrot forum> I admire Senosiain's approach, although I'd never heard of him (my problem)...not fashionable you know. That is the problem with the intellectuals of the architectural world...One needs to be in fashion!!
    Can't you just hear the Peter Yorkes of the world?

    Do keep an eye on Architectural Review (monthly) for such delights...the best architectural magazine in the world, and, no, I have no connection, it's just the journal that, over the years, has made me think...and I've been reading it since 19blip
    • CommentAuthorludite
    • CommentTimeMay 14th 2008
    thanks caliwag - don't know if senosiains is fashionable or not - who is peter yorkes?

    Just replied to u then my internet connection went down - so I'll keep it brief - perhaps we should start a new thread about favourite architects?:smile:
    • CommentAuthorludite
    • CommentTimeMay 14th 2008
    Thanks for the tip about architectural review.
    • CommentAuthorAdam0734
    • CommentTimeMay 14th 2008
    I'd have to echo the majority: sounds like the problem is with the tenants, not the house.

    Ref: "when the subject of cleaning the walls with bleach (or mould remover) came up - they said they didn't like the fumes"

    Well, apart from anything else, if they don't ventilate (ie. open windows) while they're using the bleach/mould remover, then yes, they will get hit a bit by the fumes - but then you're *supposed* to carry out that kind of work in a well-ventilated space, and this lot don't sound as though they've got sense enough to realize that. Unfortunately magic pixies will not scrub the walls clean for them; you're going to have to use some kind of bleach/mould remover, and sooner rather than later, as leaving the problem to fester will only damage the decorations.
    • CommentAuthorludite
    • CommentTimeMay 14th 2008
    Thanks adam. I have to agree, it is looking more as if the tenants are to blame. The frustrating thing is I am dealing with a person who calls himself a central heating engineer - he installs boilers and central heating systems for a living. Their excuse for not opening the windows was because they 'didn't want to heat the whole street'. It is embarrassing telling a person who thinks they are an expert, that they are totally and utterly wrong. I verbally told them how condensation occurrs, I gave them internet print outs and I had to get an expert 'impartial person' to come round and tell them. . . . . and they STILL wanted to knock a hole in our render to put in an extractor fan. . . . .

    I have to schedule a visit to give the boiler it's yearly maintainance check, and I am dreading what I'll find. I have decided that if there is any evidence of mould I will have to give them the option of either raising the rent or giving them notice.

    The people who think renting property is 'easy money', have no idea of the sleepless nights and worry it causes. :sad:

    Dare I say it, an extractor fan in the bathroom may not be a bad idea? If they are in the habit of taking long showers, especially power showers a vast amount of water vapour will be thrown into the air. You may be able to fit a fan outlet in the roof using a vent tile which would be easier and quicker than drilling through the wall. We have a rather too vigourous shower and when you step out of it the bathroom is literally dripping with condensation, yet you can stay in the bath for hours and still see yourself in the mirror!
    • CommentAuthorCWatters
    • CommentTimeMay 15th 2008
    Good article here..


    We had condensation problems in four houses we lived in so I was keen to prevent it in our self build. I installed a heat recovery ventilation system and it's been great. Personally I don't think I'd want to live in a house without one after this. Every wet room has extraction and every dry room has ventilation. Made a big difference air quality and no condensation.
    • CommentAuthorludite
    • CommentTimeMay 15th 2008
    Thanks for the link. This is the kind of information I gave to the lodgers. Most of the condensation forms against the interior of one exterior wall of the house. On the other side of this wall there is a narrow passage only 1 metre wide, then there is a high wooden fence. This passage is very cold and draughty - especially in winter, and it never gets sunlight. The expert who came to see the bungalow checked the exterior of this wall and said no damp was penetrating inside to the house, so deduced that the cold wall was making the moisture condense against the surface on the inside.

    Having read the link I am considering perhaps covering the interior surface of this wall with a warmer kind of material - such as a thin layer of polysyrene under a layer of wall paper. (I doubt many lodgers would quite go for the 70's style of a cork wall, but I probably would!)

    Incidentially, we have the minimum of tiles in the bathroom and none in the kitchen, so the walls there don't suffer from condensation at all - but it is showing me that moist warm air has to eventually cool down somewhere, it's just found the coldest place in the house to do it.
    • CommentAuthorcaliwag
    • CommentTimeMay 15th 2008
    Peter York is one of those many self-appointed fashion pundits that infest the newspapers, especially the weekenders. Trends seem to be set by bandwagonning, so they're writing about the same fashion or trend...Foster or Hadid, so that interesting and, dare I say, delightful stuff often doesn't get a look in...ever noticed how the "big" papers all seem to review the same books and CDs

    Sorry not really part of the thread, but that's a good idea to kick off a thread on relevent architects, designers, builders and craftsmen/women who are producing interesting homes. Arch Review only really does a housing issue once or twice a year but has a page every month entitled "delight" which is always good...maybe there should be design mag called "delight", mmm
    • CommentAuthorludite
    • CommentTimeMay 15th 2008
    OK. I will start one now. Think I'll call it: STUFF YOU LIKE., which should encompass, not just architects, but like you said, artists, designers, crafts people that are doing interesting things. Check out the thread on marmoleum/bamboo flooring because someone did an interesting link to a bamboo user who does buildings and furniture.:bigsmile:
    • CommentAuthorAdam0734
    • CommentTimeMay 15th 2008
    Ref: "Their excuse for not opening the windows was because they 'didn't want to heat the whole street'."

    *puzzled* Hang on. These are the same folks who only have the heating system on two hours a night? Which street do they think they're going to be heating? If it's off, it's off.
    • CommentAuthorludite
    • CommentTimeMay 15th 2008
    Yup. . . . This was their excuse!! When the expert asked them how long they had the heating on, she said "only a couple of hours a night because I'm a bit tight like that".

    I think I must be the one who is in the wrong. I spend all my time worrying that I am not providing people with a good standard of accommodation, and worrying about what will happen to our home we have rented. . . . worry worry worry. I'll just have to bite the bullet and go round and service the boiler and check out the situation. . . . it's probably much improoved since 6 months ago - after all, if it hadn't, they would have moved by now.

    Will keep you posted.
    • CommentAuthorcaliwag
    • CommentTimeNov 30th 2008
    I really think the main problem is people drying clothes on rads. bathing/showering without a fan and cooking without an extract...just think of the typical advise for pasta, the quick food of choice...bring to boil and cook with lid off. I rest my case.
    I still believe that people need education about the issue...why would you care if its not your own place, but...heat, insulation,ventilation...take one away and you suffer discomfort and/or condensation and hence mould behind furniture, beds, and on clothes. It's sure as hell not taught at school, so why would young tenants/students etc know this.
    • CommentAuthorludite
    • CommentTimeNov 30th 2008
    I think a lot of the problem our bungalow has, is because its a BUNGALOW. It has deep loft insulation and almost no ventilation - unless you have the windows open. In a normal house, the hot moist air would rise and then get dispersed due to draughts. In our bungalow, there is nowhere for it to go.

    Thanks mark-s. I think the resurrection of my post was due to SPAM too:bigsmile:
    • CommentAuthorcaliwag
    • CommentTimeNov 30th 2008
    That's surely muddled thinking Luddite. Your method moisture laden air will migrate to the first floor, which may or may not be ventilated. Sure it's more healthy to have airy bedrooms but the chances of not getting mould forming behind beds etc are remote.
    A bungalow is no different. Yes if it's tightly vent contolled and well insulated, but you still produce moisture, then you will still get mould where there is little circulation...if only on clothes, leather and stuff.
    There is no answer (other than MHVR) to extract at source and the house occupying world must be taught that...it'll only get worse as fuel bills rise....and there's no advice from our government, other than grants for the loft!!
    A text book problem with two possible solutions. (1) shoot the tenants (2) install a tumble drier with external vent and say you will evict if they continue to dry washing on rads + provide a dehumidifier on a time switch.

    The first solution is quicker and rids the world of a social problem, but can create a lot of paperwork from busybodies who crusade against natural selection.
    • CommentAuthorJackyR
    • CommentTimeDec 1st 2008
    Q: Is it natural selection if you intervene and shoot them? Surely you let the mould kill them... :tongue:
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