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.

Ludite.

Give them a months notice and find new tenants who will look after your property.

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.

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.
Frank

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 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)

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.

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?

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.

Hello

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!

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.

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.

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.

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

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.