Cavity wall insulation causing damp ?

redruby

HI I am not sure if anyone can help ?


We moved into our house approx 6 years ago and while the house was very dirty and unloved there was no signs of damp / mould at all. About four years ago we had cavity wall insulation installed by one of those government grant schemes.


Since then the mould / damp problem in the house has got really bad, the kitchen / study /utility and downstairs loo (these are all up one end of the house) are the worst affected the mould is growing from under the skirting boards upwards, its thick black and green and its a daily struggle to keep on top of it, its peeling hugs chunks of paint off of the walls and causing the skirting board to come away from the walls.


I recently cleared out a corner cupboard in the kitchen (not often used) and all the pots and dishes in there were covered in mould and the back of the cupboard itself was also covered as was the back of another cupboard we pulled out, the windows in the kitchen are terrible and if not kept clean would be covered in mould after a week.


We have a dehumidifier which is on in the worst area 24 hrs a day which at least stops the water running down the windows, and while there is someone at home the windows are always open.


I am almost sure this problem has been caused by the cavity wall insulation (we did not have the problem before) so I wanted to ask:


1 Has anyone else had this problem after having insulation put in ?
2 Can we get the company who installed it to come back and remove it ?
3 Is there anything else we can do to prevent more mould ?


Thanks in advance

DRP

Sorry this sounds like nightmare for you - there seems to be plenty of people having similar problems after getting CWI fitted (just search this forum or google it).


I would say the only/best solution is to get it removed - I read recently of someone getting CWI hoovered out of the cavity but have no idea of costs etc.

The other, potentially more effective, solution is to sell (in the summer)...

Robwiz

This sounds like a horrific problem and I don't envy you.

Some random thoughts...

In answer to question 2, yes you can. Do you have the original paperwork from the installation? There would have been a long term guarantee. It may not be worth the paper its printed on but my first course of action would be to contact the installer and have them back to check it. If they are no longer trading, there will be an umbrella organisation covering the work.

Is there anything on the outside of the affected walls that suggests there's a problem? Like damaged gutters, cracks in render or pointing or missing roof tiles? Because the water has to be getting in somehow for it to affect the insulation.

Another possibility is bridging across the top of the cavity in the loft. That's always left exposed so as not to block off ventilation of the cavity.

Are there air bricks and are these allowing adequate ventilation?

I'd get a handful of digital temperature/humidity gauges – they're cheap on the big shop and auction websites. You want the relative humidity to be kept below 70%. If you have them in several rooms you can track where in the house the humidity is high. Ventilation and air movement are key and use of a dehumidifier should help. Do everything you can to minimise the amount of steam/water vapour generated by using extractors in kitchen/bathrooms when cooking/doing washing/bathing. Don't leave towels to dry on radiators/heated towel rails – all that moisture has to go somewhere and it will condense on the coldest surfaces.

HG Mould spray is good for killing mould and preventing it coming back.

redruby

Hi Thanks for the replies, I do have the original paperwork which I dug out today, will contact the firm tomorrow to try and get the ball rolling re removing it for us, do you know if the company will pay anything towards redecoration ? There is such a lot to re decorate (having not long done it all) that I am not sure we could even afford to do it.


I cant see anything on the outside, broken gutters etc, but I will get the OH to check tomorrow, I am sure he would have said if there was something though. I will get him to check the bridging in the loft too. Also I am not 100% sure I have even seen an airbrick will check that out too.


I will order some of those gauges tonight would be interesting to see the results.


I do dry the washing outside as much as possible but sometimes it has to be done inside, we are also looking at a tumble dryer to try and avoid drying washing on the rads.


Thanks again will keep you posted !

[Deleted User]

Cavity wall insulation is underwritten by an organisation called GIGA, Cavity Insulation Guarantee Assoc. They have a notorious reputation as a load of shysters who find any excuse not to pay out, which is why I've shied away from having CWI. Search for CIGA and you'll find it all.

cyclonebri1

You cannot remove foam injected or blown in CWI with 100% effect, even particulate insulation will have settled and "matted" after 4 years.

Good look if you think you can, but you'd be taking the word of the people you have had install it, and just how much effort would they be expected to put into removing it?.

Also, the advice so far has nothing to support it. It is far from clear that your damp, or CONDENSATION issues are as a result of the remedial work, water would have to be running down the exterior for any penetration of the magnitude you describe to occour.

You need to increase both the heating and ventillation, your dehumidifier, albeit giving some degree of assistance, is treating the symptoms not the disease.

The only other and 3rd antidote to condensation is insulation, however in your case maybe the added insulation has reduced the ventilation and negated it's benefit.

redruby

cyclonebri1 wrote: »

You cannot remove fom injected or blown in CVI.

Good look if you think you can.

Also, the advice so far has nothing to support it. It is far from clear that your damp, or CONDENSATION issues are as a result of the remedial work, water would have to be running down the exterior for any penetration of the magnitude you describe to occour.

You need to increase both the heating and ventillation, your dehumidifier, albeit giving some degree of assistance, is treating the symptoms not the disease.

The only other and 3rd antidote to condensation is insulation, however in your case maybe the added insulation has reduced the ventilation and negated it's benefit.

Thanks for this, I understand that the dehumidifier is not treating the problem but it helps to not make it worse.


Also these problems have only started since we had the CWI put in and out heating / ventilation has not changed. Which is why I assumed it was all connected, otherwise why did we not have the problems for the first two years ish ?

cyclonebri1

Ok, look, there is a very simple and FREE test you can perform yourself to determine the source of the moisture.
Actually thats wrong, it will determine if the moisture or water vapour is coming through the walls or from the atmosphere.

You should repeat this in several areas in the room/house.

You need a piece of clear polythene with NO holes in it about say 12" square. A thick rubble sack or similar is ideal, but again it must not be perforated.

Dry off the test site with a towel and a hair dryer when the house is at it's warmest.
Carefully tape the sq to the wall all around the 4 sides ensuring an airtight seal is made. Duct tape or similar is ideal for this.
Leave it over night, if there is any moisture penetration it will show as condensation on the inside surface of the sq, any moisture on the outside or none at all indidcates it is from a source of internal condensation, ie, it's not damp from within the wall or from the outside of the house.

It's a common trick that we used to employ when damp was suspected in solid floors under carpet.

Back to your issue, I still feel that the cavity was venting the house previously and that it now isn't
My question is, is the house warmer now than it was with the same degree of heating before the CWI was fitted?, or have you had to turn the heating down?, or has it made no difference?, ( I supose that's 3 questions really:D)

force_ten

what can happen with the cavity wall insulation is if it gets damp it creates problems

is the wall that is the worst problem south westerly or west facing and what sort of condition is the wall in is it brick and what sort of condition is the pointing in ?

is the wall subjected to wind driven rain ?

and what sort of survey was carried out at the time the insulation was installed

what can happen with cavity wall insulation is if it becomes damp then it can cause cold bridging making the inside walls colder than they should be and susceptible to condensation

damp insulation in the walls is a major problem and will cause either penetrating damp or excess condensation on internal walls

first port of call for you is back to the company that installed the insulation and see what they have to say

if you get no joy with them then go to

www.ciga.co.uk

and speak to them about it

redruby

cyclonebri1 wrote: »

Dry off the test site with a towel and a hair dryer when the house is at it's warmest.
Carefully tape the sq to the wall all around the 4 sides ensuring an airtight seal is made. Duct tape or similar is ideal for this.
Leave it over night, if there is any moisture penetration it will show as condensation on the inside surface of the sq, any moisture on the outside or none at all indidcates it is from a source of internal condensation, ie, it's not damp from within the wall or from the outside of the house.


)

Thanks for this, OH just going to see if we have a rubble sack in the shed and we will leave it overnight and report back in the morning, I am really interested to see the results !

redruby

force_ten wrote: »

what can happen with the cavity wall insulation is if it gets damp it creates problems

is the wall that is the worst problem south westerly or west facing and what sort of condition is the wall in is it brick and what sort of condition is the pointing in ?

is the wall subjected to wind driven rain ?

and what sort of survey was carried out at the time the insulation was installed

what can happen with cavity wall insulation is if it becomes damp then it can cause cold bridging making the inside walls colder than they should be and susceptible to condensation

damp insulation in the walls is a major problem and will cause either penetrating damp or excess condensation on internal walls

first port of call for you is back to the company that installed the insulation and see what they have to say

if you get no joy with them then go to

www.ciga.co.uk

and speak to them about it

Hi thanks for the reply, the wall in question is north facing and not joined to anything on that side so does get driven rain, as far as I can see the pointing is ok, there are no gaps in it as far as I can see.


When the chap came to do the survey he walked around the outside of the house for a few minutes, then came in and looked at the inside, he asked us to block up two fire places that were not in use and then signed it off as ok.


I will contact the people who put it in today but don't expect to her back from them any time soon.


The thing that gets me is that the mould has got behind the fixed kitchen units and is working its way into the cupboards, obviously we cannot take them all out to have a look but the smell in the cupboards is terrible


Thanks again for the replies