Damp problems after cavity wall insulation

[Dampgone]

We have lived in our 3 bed roomed detached house since when it was first built in 1972. Over the years, we have added full central heating, double glazing throughout and new upvc soffit and fascias.

Two years ago, we had cavity wall and loft insulation. This made the house lovely and warm! However, last winter we found that the amount of condensation on the windows had increased, plus we noticed wet patches on some of the ceilings next to exterior walls. In our bedroom the wet was actually running down the wall from the ceiling. Also, when my husband checked in the attic, everything was absolutely wet through. We put these problems down to the excessively cold winter that we had during 2009/2010.

We were horrified when, during October this year, we noticed the same problems had re- appeared. I contacted the company who installed the cavity wall and loft insulation by e-mail and attached photos of the problems. However, they have never got back to me – typical, they’ve had their money for the job! We think that the surveyor should really have identified potential problems when he came to survey the property for suitability for cavity wall insulation.

My husband asked a neighbour, who had been a builder before he retired, if he knew of anything that might help. He suggested that we put ventilation in the soffits. My husband bought 30 x 70ml round air vents which he fitted at equal intervals along the soffits. He got these from a local diy firm; they cost £2.75 for a pack of 10.

It was the best money we’ve ever spent! The ceilings are dry; the attic is dry and it is only on very cold or damp days that we get the minimum of condensation on the windows. Amazingly, it has cured the condensation on the windows downstairs as well as upstairs. When we know that the weather is going to be really damp and cold, we make sure that we leave interior doors open when we go to bed, in order to circulate air, plus open the curtains slightly at night in rooms that we aren’t using. This proves to us that you must have air flow in every room.

We cannot believe the difference installing these little devices has made and wanted to share this with anyone else who may be experiencing similar difficulties. This was to be our first step in trying to rectify this problem ourselves – we were considering window vents, de-humidifiers etc. Thankfully we don’t need to do anything else. Hope it works for you!!!

[hawkers]

Thankyou for your information, I too am suffering excessive condensation and damp problems on walls after having cavity wall insulation done this summer.

I have never had these problems before in my house.

I will seek to put your idea in practice and post back sometime with my results.

Regards

David

[emwebb27]

We have damp patched on our bedroom ceiling and spare room ceiling near the outside walls, which are getting worse daily. The attic is dripping wet as well! We had cavity wall insulation in april this year and attic insulation the year before. We have, had some vents fitted in the roof as we were told this would be helpful as we have had a similar problem before. We have also had a number of roofing experts around who told us various things. We paid last year for some roofing tiles to be replaced.
What else do peole suggest we do. What could be the cause?
Emma

[Dampgone]

Hello David

I sincerely hope that this works as well for you as it has for us. I would be very interested to know your results.

Regards

[Dampgone]

Hello Emma

We put 30 vents in the soffits in order to circulate air up and into the attic. There has to be sufficient air in the attic to keep it dry. Since we fitted the vents in the soffits our attic and ceilings have been dry.

Good luck - I know what a nightmare this is!

Regards[/b]

[belfastjoe]

Hi folks i too have similar probs with damp in the corner ceiling in my spare room on the outside corner and along the outside wall on ceiling in the bathroom after having cavity wall insulation,,,we also get alot of condensation on windows,,,,i have researched this and was thinking of putting in an air circulation system which basically sucks air out of attic and circulates it around around the house but this is more expensive than option u have mentioned,,,,my only concern is the amount of cold/draughts that will come in and also how the air circulates from ur attic to the rest of the house/

regards joe

[Dampgone]

Hi Belfastjoe

I would recommend that you try what we did before going to the expense of an air circulation system. We are completely unaware of how this works, but I can assure you that, for us, it has.

Last year when my husband went into the attic to get the Christmas decorations out, it was absolutely wet through. This year, despite the extreme cold, snow, ice etc that we currently have, the attic was cold but dry. So are the ceilings and walls. We do still get some condensation on the windows on extremely damp/cold days, but nothing like we had been experiencing.

If you are able to install the vents yourself, it will cost you very little and we saw results within a couple of days. If it doesn’t work for you as it has for us, you can always look at alternatives.

You ask if it has caused cold or draughts in the house. I can honestly say that I haven’t noticed any difference. As to how it works for all the house – even the downstairs windows – I really haven’t a clue, but it did.

I really hope it does for you too.

Regards, Barbara.

[colli]

Hi If you get this message I have the same problem after having cavity done in my Bungalow, could you tell me where to buy and the size of the vents you brought call me thick but dont know what they look like

[Dampgone]

Hi Colli

We got the vents from a company called Screwfix – http://www.awin1.com/awclick.php?mid=12 ... rewfix.com. They are called circular soffit vents and are available in white or brown.

They are £2.81 per pack, or £2.40 per pack if you buy 5 or more packs. The reference number is 68936 for the white ones and 96495 for the brown ones.

You will also need to purchase a 70mm diameter hole cutter, reference 19804, at £6.17 if you do not already have one.

If you go to the website and type in the reference numbers in the “search for” box you will be able to see what they look like.

Good luck!

Regards, Barbara

[rslater100]

Moved into house 6 months ago. It has previously had cavity wall and loft insulation installed. The property is 1960's. We have mould patched appearing in one bedroom in the corner on the walls and ceiling of the external wall. There is also mould spots behind the bed. There is also mould appearing in the bathroom on the ceiling in the corner of the external wall. The loft is dry and I have exposed the top of the plasterboard and there is no damp. I have cleaned the gutters out but due to the roof overhang they are lower than where the mould is appearing. There are gaps in the soffit to allow ventilation into the roof.

Ther is no insulation in the roof overhangs could this be the problem?

[SPUD1701]

Moved into house 6 months ago. It has previously had cavity wall and loft insulation installed. The property is 1960's. We have mould patched appearing in one bedroom in the corner on the walls and ceiling of the external wall. There is also mould spots behind the bed. There is also mould appearing in the bathroom on the ceiling in the corner of the external wall. The loft is dry and I have exposed the top of the plasterboard and there is no damp. I have cleaned the gutters out but due to the roof overhang they are lower than where the mould is appearing. There are gaps in the soffit to allow ventilation into the roof.

Ther is no insulation in the roof overhangs could this be the problem?

Same principle as previous this still sounds like copndensation, but rather than being due to lack of roof ventilation, you appear to have a lack on ventilation in the rooms.

Bedroom make sure you either have trickle vents to windows or brick vent in wall to outside air, pull bed away from wall to let fresh air circulate.

Bathroom - lots of moist air - vent and fit mechanical extracor to help remove moisture

[rslater100]

Moved into house 6 months ago. It has previously had cavity wall and loft insulation installed. The property is 1960's. We have mould patched appearing in one bedroom in the corner on the walls and ceiling of the external wall. There is also mould spots behind the bed. There is also mould appearing in the bathroom on the ceiling in the corner of the external wall. The loft is dry and I have exposed the top of the plasterboard and there is no damp. I have cleaned the gutters out but due to the roof overhang they are lower than where the mould is appearing. There are gaps in the soffit to allow ventilation into the roof.

Ther is no insulation in the roof overhangs could this be the problem?

Same principle as previous this still sounds like copndensation, but rather than being due to lack of roof ventilation, you appear to have a lack on ventilation in the rooms.

Bedroom make sure you either have trickle vents to windows or brick vent in wall to outside air, pull bed away from wall to let fresh air circulate.

Bathroom - lots of moist air - vent and fit mechanical extracor to help remove moisture

Thank you for your help, I will put a vent into the bedroom and bathroom to see if this helps.

[dampgone2]

I have similar problems with condensation on walls and ceilings. You mention using air vents in the soffits - but I am not sure what you mean by soffits? I know what soffits are (the underside of an item), but soffits of what in this case?

[spratster]

hi all i had the same problems with mould growth and condensation around 18 months ago after cavity wall and loft insulation ! i live in leeds and found a local firm called CavAid that had been recomended to me , they came out surveyed my house for free !
they quoted me £162 for soffit ventilation , and to remove excess loft insulation from around the edge of the loft ?
money well spent in my opinion !!! since then the damp upstairs has gone along with the black mould , and condensation !!