Damp problems with CWI

[David]

After over 10 years promoting CWI I have always been aware of the potential for damp problems arising from CWI but only encountered my first potential case yesterday. I would be grateful for any advice colleagues can give. What evidnece can /should residents obtain? What is the best way to deal with installers and CIGA? This was a Warmfront job do they have responsibility in this?

The resident has had damp penetrtation and mould growth over various parts of the external walls. The is also signifcant condensation on the windows in colder months. A family friend has been in the loft and noted that the insulation was over the eaves. They have purchased a dehumidifier but not sure this will resolve the issues. I would be more inclined to have recomended ventilation (HRV or passive input) but would be reluctant to advise something that is so costly if it didn't solve the problem.

So far I have advised them to contact the installer? Do I need to involve anybody else (building control, BBA, trading standards)?

[ALEO Admin]

Hi David

I've had an email response from Denise Marsdon, who suggests that you complain to the Installer in the first instance and then CIGA in writing.

Denise also provided a link to the to CIGA advice at http://www.ciga.co.uk/complaints.html

Best Regards

Rob Leeson
CAN National Secretariat

[ALEO Admin]

... I've also had the following response from Richard Cassells:

A project I was involved with had the same problem, a block of flats built in 1980 and was filled with a fibre CWI. The installer company had not been aware that the mortar joints in the walls had failed because of the lack of cement or bad mixing at the time of construction, water ingress made a cold bridge with mould and damp becoming the main problems, the solution was to apply EWI. from time to time a property with this problem may pop up.

The installer must have a warranty if he carried it out for Warm Front as it is required.

Thanks to everyone who has responded. hope this helps

Rob Leeson
CAN National Secretariat

[ALEO Admin]

Hi David

Below are another couple of responses, thanks to Hazel Hill and Joanna Brooks.

__________________

I have also had one job go " pear -shaped" in 13 years.

I worked with both environmental health officers to establish whether it was life style related or caused by the CWi . This does take time to establish.

I worked with the installer which who where part of the snug network and we were able to remedy this.

The cause was rubble in the cavity bridging the damp proof course.
The solution was drillling out bricks, the rubble and refilling.

However from start to finish this has taken two years to rectify completely.

Regards
Hazel


__________________


Just saw this message from UK-CAN and wondered if you could pass this on to David. I am really surprised this is the first case of damp David has come across, working in an exposed coastal community I have seen my fair share of failed CWI that has caused damp problems inside, but in most cases the situation can be resolved (but it will take time and persistence with the installer). Please advise David that while CIGA can get involved if the installer is no longer or refuses to take responsibility, but in the first instance it’s totally down to the installer to resolve the issue. I have called CIGA out for an independent opinion on a CWI damp issue before, but that is pretty much a last resort for them.

In most cases I always argue on behalf of the resident directly with the installer that the installer’s company should pay for the insulation to be extracted, as most of the time the damp is because there is a physical problem with the house and in my opinion it should not have been installed in the first place anyway (well at least not without fixing the problem). If you need a second or more independent opinion, you could always contact one of the few extraction companies to ask their view on the failure.

The installer will probably try and blame the residents and say it’s a condensation problem (of course this must be ruled out before pursuing any complaint as I have come across some ludicrous situations with extreme laundry drying or dog washing going on inside the house).

So assuming residents are living sensibly (heating and ventilating appropriately etc…) and if there is no obvious sign from the outer wall why there is damp (i.e. failed pointing or really bad pointing), then it’s possible that there is some scum in the cavity causing thermal bridging or there is something up with the wall ties. If there is scum in the cavity or bad pointing, then I argue that the installer did not survey adequately and should never have installed in the first place (hence it is their responsibility to fix it). Of course in exposed locations it can just be purely penetrating damp that has saturated the mineral wall that is causing the problems inside during the winter, but I’m pretty sure that risk should also have been taken into account at the survey stage and so it’s still the installers fault. Invariably and from my experience I would say it is not normally a good idea to re-fill unless the problem has been identified and fixed, however once the wall has dried out and if the problem is most likely just being exposed, then one solution could be to re-fill with a EPS bead product rather than mineral wool as EPS can’t hold any moisture and therefore seems to suffer less when used on exposed walls that might suffer from penetrating damp. I don’t believe I have ever had a damp complaint from a house with EPS product used for CWI, even right on the sea front!

By the way, I understand it is probably the installer not Warm Front that are responsible for this, from my previous experience I doubt you’d get anywhere chasing this with Carillion through the WF team.

Hope that is helpful,

Regards

Jo

[Technitherm]

I too am surprised that this is the first time you have experienced this problem as we regularly receive calls to assist/provide a remedial solution where standard CWI materials have failed. The obvious solution is to do it right first time using only a material suited to severe wind driven rain exposure conditions and meeting the requirements of BRE water penetration and flood resilience testing, particularly if the building to be treated is in a coastal region. For further details visit our website below.There is no option but to remove the saturated material at the earliest opportunity if you wish to prevent additonal problems occurring, for example, corrosion of wall ties. Unfortunately, to do this you will have to follow the normal route requiring investigation, installer, etc outlined by others above.

Kind regards

Mervyn

Mervyn Kirk
Director
Energy Efficiency Solutions

Isothane Ltd.,Newhouse Road, Huncoat Business Park, Accrington,Lancashire. BB5 6NT
(Mobile) 07889 725211 +44 (0)1254 872555
mervyn.kirk@isothane.com www.isothane.com

Technitherm® - Cavity Wall Insulation For Hard-To-Treat/Non-Standard Cavity Walls

[David]

Hi Everyone

Thanks for the feedback. It turns out the problem all stemmed from the loft insulation being all over the eaves. This has been rectified now and the problem seems to have resolved now. Unfortunately the firm involved did not think they owed the home owner any compensation for the redecoration costs, which is a shame. Then again that will inform us on their customer care policy in-action!

Regards

David