Your Questions Answered Condensation
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WHO IS LIABLE FOR DECORATION?
Who is liable to pay to repair and redecorate after damage due to mould of condensation dampness, landlord or tenant?
Question:
WHO IS LIABLE FOR DECORATION?
Who is liable to pay to repair and redecorate after damage due to mould of condensation dampness, landlord or tenant?
Submitted by: A Mohamed
Answer:
The answer to your question is 'it depends'. If the landlord has failed to provide sufficient permanent ventilation and adequate powered extraction in the kitchen and bathroom then it is possible that a case could be made against the landlord.
If on the other hand the lifestyle of you and the other occupants in the house is such that excessive water vapour is generated resulting in condensation and mould growth then this would very likely be down to you. You should seek a legal opinion. Have you tried using a domestic dehumidifier?
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WALLS BLACK, CLOTHES COVERED IN GREEN MOULD
I have been living in a flat roof property for 6 months. I have redecorated the property but in my daughters room the walls are turning black with damp. The bed has been moved to the middle of the room because of this and also the bedding was getting wet if it was against the wall. I have also had to take the chest of drawers out of the room as the clothes inside had green mould on them. This also happened with the clothes in the wardrobe. The houses have been noted for being damp in the past. My daughter’s room has an air vent also the window is always on the latch. The property has an airflow system fitted. I have been told by the housing association that it is condensation in my daughter’s room. I disagree with this, could I be right? I also have damp in my bedroom as the roof is leaking
Question:
WALLS BLACK, CLOTHES COVERED IN GREEN MOULD
I have been living in a flat roof property for 6 months. I have redecorated the property but in my daughters room the walls are turning black with damp. The bed has been moved to the middle of the room because of this and also the bedding was getting wet if it was against the wall. I have also had to take the chest of drawers out of the room as the clothes inside had green mould on them. This also happened with the clothes in the wardrobe. The houses have been noted for being damp in the past. My daughter’s room has an air vent also the window is always on the latch. The property has an airflow system fitted. I have been told by the housing association that it is condensation in my daughter’s room. I disagree with this, could I be right? I also have damp in my bedroom as the roof is leaking
Submitted by: S Fleming
Answer:
I know that this is not what you want to hear but everything you describe sounds like condensation is the cause. The amount of moisture/water vapour released into the atmosphere from a localised leaking roof is negligible when compared with one breath of a person so a leaking roof is unlikely to be responsible for the situation in your daughter’s bedroom. The winter months are the worst for condensation which is the period you have been living there. During the summer the problem will disappear but unless things change it will all return next winter.
Poorly insulated and inadequately heated properties will be more prone to the effects of condensation. It is likely that the flat roof is not well insulated and if the external walls are solid then insulation options are significantly reduced. If you have read about condensation on our web site you will have realised that condensation is the result of the life style of a property's occupants - it is not caused by the property. It is also acknowledged that some properties are more prone to condensation than others, flat roofed properties being amongst them.
You need to look very carefully at all the activities you do in your property that produce water vapour:
Breathing - not a lot we can do about this!
If you dry clothes anywhere inside the property this should stop immediately - this is one of the worst causes of condensation.
Adequate powered extractors should be fitted and used in the kitchen and bathroom and both areas used with the doors closed.
Constant dry heat should be used in all areas - not just short sharp bursts.
Does any excessive cooking or washing take place in the property?
Are tropical fish tanks present?
You may also want to consider running a domestic dehumidifier. They are not expensive to run - like a fridge - and very effective.
Hope the above is of some assistance to you.
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MOULD IN WARDROBE
My daughter's 1950's semi detached house has a built in wardrobe that incorporates two outside walls. There is no 'lining' of the wardrobe - the outside walls of the house are the back and side of it. The clothes in the wardrobe feel slightly damp and there is a small patch of black mould in the bottom corner. I am thinking of insulating the wardrobe by using something like polystyrene sheet of the type used for concrete floors and then facing this with plywood. I'm also thinking of combining this with the installation of an air brick into the inner leaf of the cavity wall, in the area where the mould is, to improve ventilation. Any advice on this proposed approach would be appreciated.
Question:
MOULD IN WARDROBE
My daughter's 1950's semi detached house has a built in wardrobe that incorporates two outside walls. There is no 'lining' of the wardrobe - the outside walls of the house are the back and side of it. The clothes in the wardrobe feel slightly damp and there is a small patch of black mould in the bottom corner. I am thinking of insulating the wardrobe by using something like polystyrene sheet of the type used for concrete floors and then facing this with plywood. I'm also thinking of combining this with the installation of an air brick into the inner leaf of the cavity wall, in the area where the mould is, to improve ventilation. Any advice on this proposed approach would be appreciated.
Submitted by: BKR
Answer:
Rather than polystyrene and ply we would suggest that you use insulated plasterboard that incorporates a vapour check on the warm side. (This is very important otherwise condensation could form on the wall behind the insulation). This may be cut to size and glued up using 'no more nails' or similar. A vapour check is very important and your method did not appear to have one. We would not bother with the air vent as the insulation would make this unnecessary. (Either one or the other)
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MOULD IN BEDROOM
My bedroom window gets a lot of condensation on it even though it is double glazed. I don’t usually have any heating on in the bedroom (I have electric storage heating) and by the morning the windows are running with water. Over the last couple of months a black mould has started to appear about half way up the back wall which backs on to the stairwell up to my flat as well as the wall under the window. I have to clean it every day. If I leave it for more than one day anything that is on the floor also gets mould growing on it,even my shoes. What can I do to stop and cure it?
Question:
MOULD IN BEDROOM
My bedroom window gets a lot of condensation on it even though it is double glazed. I don’t usually have any heating on in the bedroom (I have electric storage heating) and by the morning the windows are running with water. Over the last couple of months a black mould has started to appear about half way up the back wall which backs on to the stairwell up to my flat as well as the wall under the window. I have to clean it every day. If I leave it for more than one day anything that is on the floor also gets mould growing on it,even my shoes. What can I do to stop and cure it?
Submitted by: Jenny
Answer:
What you describe is almost certainly condensation and it is the life style of the occupants that is causing/generating the water vapour that eventually forms as condensation. Why is the heating off in the bedroom? Leaving it on will help as warm air is able to support more water vapour so less will be deposited on the window/walls/clothes. Do you dry your clothes inside? If you do then stop this immediately as this is probably the main cause. Do you have extractors in the kitchen and bathroom? Are they working? You should also consider purchasing a domestic dehumidifier and run this when the air is warm with all of the windows closed. Are our questions on the right trail?
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HOW DO I PREVENT INTERSTITIAL CONDENSATION?
Can you describe to me please how interstitial condensation is to be prevented within the external walls and roof construction? Without any necessary calculations.Question:
HOW DO I PREVENT INTERSTITIAL CONDENSATION?
Can you describe to me please how interstitial condensation is to be prevented within the external walls and roof construction? Without any necessary calculations.Submitted by: Maria
Answer:
To prevent interstitial condensation forming one needs to install vapour checks in correct positions. Within a roof we would tend to consider this to be surface condensation due to inadequate ventilation or incorrect construction. We consider interstitial condensation to be that which forms within a material, usually due to a declining temperature gradient in that material, i.e. in the middle of a solid brick wall.
Please forgive us if we are not understanding what you require correctly.
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WHAT IS INTERSTITIAL CONDENSATION? (CONDENSATION)
My contractor says I have interstitial condensation. What is this? Question:
WHAT IS INTERSTITIAL CONDENSATION? (CONDENSATION)
My contractor says I have interstitial condensation. What is this? Submitted by: Rob Jones
Answer:
Most of us are familiar with visible surface condensation that forms on the inside of windows and wall surfaces during cooler weather. This happens because the glass or wall surface is at or below the ‘dew point temperature’, (the temperature at which water reverts from its gas state to a liquid) relevant to the environment in which they are present. Interstitial condensation is still the process of water reverting from its gas state to its liquid state, but the difference is that the point at which this occurs is within the thickness of a wall or ceiling (rather than on the surface).
Most walls in residential properties are porous and allow water vapour to pass through them. This is one of the main ‘escape routes’ of water vapour from the inside of a property to the outside. In a solid wall there will be a declining temperature gradient between the usually warmer inner wall surface and the exterior. Interstitial condensation will form when the dew point temperature is within the thickness of the wall or ceiling and the water vapour passing through the wall reaches that point.
If the resistance to the passage of water vapour and heat conducting properties of the building materials used in your property are known, then it is possible to calculate at what point interstitial condensation will occur within say a wall. It should be appreciated that this is a risk calculation only that uses prescribed internal and external conditions and the whole procedure is outlined on BS 5250; 2002. Has your contractor made these calculations to arrive at his conclusion?
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HEAT RECOVERY FAN (CONDENSATION)
I had replastering works done about 4 months ago. I then tried to have my decorator paint the area but she refused saying that it is still damp. Is this normal? I have one quote from a damp proof agency that states that we also need a heat recovery fan to stop condensation. Do you have any comments on the heat recovery fan? Question:
HEAT RECOVERY FAN (CONDENSATION)
I had replastering works done about 4 months ago. I then tried to have my decorator paint the area but she refused saying that it is still damp. Is this normal? I have one quote from a damp proof agency that states that we also need a heat recovery fan to stop condensation. Do you have any comments on the heat recovery fan? Submitted by: Ann Robinson
Answer:
It is difficult to answer your question without knowing more specific details. You do not state where in the property or the reason why replastering was undertaken. If the new plaster was applied onto a dry surface then one would expect it to have dried after 4 months. If it was because the area was damp then what caused the damp and has its source been eliminated? Your decorator is correct not to cover a damp surface as to do so would be a waste of time and money.
You also state that a damp proof company has recommended a heat recovery fan to stop condensation. Has active condensation been diagnosed in your property? At various times of the day has someone taken relative humidity readings, the air temperature, established the dew point temperature and taken wall surface temperature readings to see if they are above or below the dew point temperature? Have any other condensation monitoring procedures been used? Do you suspect condensation is a problem?
Condensation is a consequence of life style i.e. how you live in your house and your water vapour generating activities such as internal clothes drying, cooking without extraction etc. Some properties are more susceptible to the effects of condensation than others. A heat recovery fan, if installed correctly, may contribute towards the control of a condensation problem. How effective it will be is dependant upon the severity of the problem. It may be sufficient on its own but it is possible that other control measures may also be necessary or perhaps, subject to the circumstances, be even more effective than a heat recovery extractor.
If you would like to supply more details about your problem(s) we should be able to provide you with a more informative answer.
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RUSTY WET NAIL AND MOULD? (CONDENSATION)
In the 2nd bedroom of my bungalow there was black mould on the wallpaper and a rusty wet nail in the skirting board on the outside wall. On removing the paper the plaster was dry with no sign of damp or mould. Could you suggest what has happened to the skirting board please? Question:
RUSTY WET NAIL AND MOULD? (CONDENSATION)
In the 2nd bedroom of my bungalow there was black mould on the wallpaper and a rusty wet nail in the skirting board on the outside wall. On removing the paper the plaster was dry with no sign of damp or mould. Could you suggest what has happened to the skirting board please? Submitted by: Mike Green
Answer:
Of course you should check outside first for any potential causes of damp penetration. From what you describe however it sounds very much like condensation is the cause of your problem. Mould will normally only grow on a wall where there is a pure water source such as rain water, tap water or condensation. It will not grow on surfaces where the water has originated from the ground - such as rising damp as this contains salts and minerals which act as a 'mouldicide'.
Bungalows are notorious for suffering the effects of condensation. Spare bedrooms can suffer badly – especially north walls. Condensation is caused by lifestyle – i.e. what you do in your house - and probably the single biggest contributor is drying clothes internally on and against radiators. This bad practice will affect all rooms even if you do not dry the clothes in the room in question. The condensation season is November to March and very probably during the summer you will not experience a problem. The rusty nail head is likely to be due to condensation forming on it since the nail head will be colder than the surrounding wood.
Look at everything that you do that produces water vapour - cooking, washing, clothes drying etc. and extract as much water vapour as possible directly to the outside at source. Insulate the property well especially cavity walls. If you insulate the walls the inner skin of brickwork will be warmer and therefore less prone to the effects of condensation.
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CONDENSATION ON DOOR FRAME (CONDENSATION)
I just installed a new garden door in my house, where the old sliding door was. In the basement I have a gas stove that I use to heat the basement. Now the problem is that when the gas stove is on then I get a lot of condensation on the metal frame of the door and it is getting on the living room floor.
Question:
CONDENSATION ON DOOR FRAME (CONDENSATION)
I just installed a new garden door in my house, where the old sliding door was. In the basement I have a gas stove that I use to heat the basement. Now the problem is that when the gas stove is on then I get a lot of condensation on the metal frame of the door and it is getting on the living room floor.
Submitted by: Victor Turpin
Answer:
You do not state the type of gas stove you have but if you have a portable calor gas type of heater then we are not surprised that you are getting condensation as this type of heater produces vast quantities of water vapour as a product of combustion. All gas combustion produces water vapour and other bad gasses so you need to make certain that the area in question is adequately ventilated when the heater is on and we would recommend that you install a Carbon Monoxide detector - it could save your life. Metal door and window frames always tend to suffer from condensation even if no where else does since they conduct heat/cold very well. Some actually have a thermal break in built to help reduce this.
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CONDENSATION ON WINDOWS AT 45% RH? (CONDENSATION)
In our house we have new, very tight double glazed windows. The HVAC system is hot air with adjustable humidification. When I raised the humidification to 45% (because our plants were suffering from dryness), the condensation on the windows produced significant pooling of water at the bottom of the glass. Is there anything to do?
Question:
CONDENSATION ON WINDOWS AT 45% RH? (CONDENSATION)
In our house we have new, very tight double glazed windows. The HVAC system is hot air with adjustable humidification. When I raised the humidification to 45% (because our plants were suffering from dryness), the condensation on the windows produced significant pooling of water at the bottom of the glass. Is there anything to do?
Submitted by: Franz Allina
Answer:
Do not be totally hung up on the relative humidity reading alone.The varying temperature within the property will change the relative humidity without adding or taking away any moisture. Relative humidity will increase if temperature falls and could therefore give rise to your situation. We suggest that you check the humidification regulator is functioning correctly and is correctly calibrated. You do not state if it is condensation forming on the glass or the frame or both. If your double glazing is new does it not have trickle ventilators built in? If not then try cracking the window open just a little to enable some ventilation. Also make certain you do everything possible to remove excess water vapour generated at source i.e. powered extraction in the bathroom and above the cooker and NO clothes drying inside - EVER! Remember it is what you do in your home that produces the water vapour that eventually forms as condensation.