Attic Attack

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A couple of weeks after CIGA had determined that the installation was done to specification I gained access to the loft space with a ladder. It's not the easiest space to see though but I know the Home Buyer's surveyor had looked around and taken a photo and only really commented on presence of a cold water cistern.
I was horrified to find the white wool overflowing from the cavity into the loft space with soggy wool in the cold water cistern and the overflow tank.
Given that the wool is known to be a skin and respiratory irritant, I was not pleased to be bathing in this stuff.


Nasty wool overflowing into the loft space
Happy christmas from your liquidated cavity installation company


Overflow tank with soggy wool.
We also found wool under the bath panel - if the bath overflowed at anytime then there is a massive gap underneath open to the cavity with wool poking out of it.
It's pretty clear that the installer made a right mess and should be liable for cleanup. As the installer is no longer trading, that responsibility falls on CIGA.

CIGA guidance to installers regarding roof spaces and under baths


CIGA's own guide  "Technician’s guide to best practice Version 2.0 - Issued July 2002"
http://uk.siggroup.com/media/1205/ciga-installing-cwi.pdf
Covers this issue and the above findings show objective proof of complete lack of pre and post internal checks.

(I've highlighted the salient points in bold).

PRE-INTERNAL CHECKS

Sealing the cavity
Check for fuse boxes open to the cavity, and seal any large holes or gaps that you find. You should also seal any large gaps around the pipework under baths and sink units. Check if any other cupboards, wardrobes or domestic appliances have been built into the cavity.

Roof space
Gain access to the roof space – taking care not to tread on plasterboard ceilings. Inspect the gable ends; particularly the detailing around joists, purlins and binders. Any gaps or holes in the masonry should be sealed with mineral wool quilt to prevent the insulant from being blown into the loft. Ensure that airbrick ventilation is maintained.


POST-INTERNAL CHECKS

Check the whole building to ensure no insulant has entered. If any insulant has entered the building or roof space - clear it away!

Effect on density calculation

Clearly the installer thought this wool was actually in the cavity. If the product was correctly installed to CIGA's guide then a density box test must be performed to verify the density of product before starting and an installed density check calculation done after.


As the density calculation depends on the amount of material blown into the wall, the fact that so much escaped would suggest that the calculation if done by the installer was off by a fair amount which suggests a defective installation.




The calculation below states that at least ten cavity width measures should be performed. I find it hard to believe that a company who didn't even check the loft would go to the bother.


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