Attic Attack

-
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.


Comments

Post a Comment

Popular posts from this blog

The controversy over Cavity Wall Insulation 'topups'

-
Image
In this article I talk about the practice and problems of topping up insulation when voids are discovered, why it is being done and the potential violations of building regulations. I can only put forwards what I have understood from public documents and personal correspondence  So I welcome corrections or clarifications from the industry on this important issue for home owners and will happily update this post to reflect any inaccurate statements. We know that 100s of topups are done every year.   From what I can gather : If the BBA have not approved these topups then the relevant local authority building control should have been notified prior to topping up as an 'off licence' use of the product.  It is not clear that the correct procedures are being followed in all cases. Background :Voids are common A void is simply an area cavity between the walls which is missing insulation.  If a void is large enough then the insulation will not be compliant with the meter square
Read more

CWI, Impermeable masonry paint, hard cement and breathability

-
Image
Waterproof or let's call it plastic masonry paint made with silicone or acrylic sounds like a fantastic idea to keep that pesky rain away from the wall. Unfortunately it can easily cause the opposite in terms of moisture management and inflict devastating damage to old solid walls which were originally made with a breathable building envelope. This article serves as a discussion to highlight some of the unexpected problems which show up in the real world verses the limited testing of the BBA certificates and I welcome discussion from anyone interested in this subject. For a good 'primer' on the problems associated with plastic paint in solid walls, Peter Ward from Heritage House has a number of videos of detailing the sacrilege caused by often well meaning tradesmen applying these aggressively marketed products. I recommend watching all his videos especially if you are having any sort of damp problems so that you can avoid the multimillion pound interventions sold by 
Read more

Discrepancies between Internal and external DPC (damp proof course)

-
Image
In a cavity wall construction, one would expect that the damp proof membrane to be at the same level on both walls. It turns out this is not always the case and my house is a good example where the internal wall's DPC is more than a brick lower than the external wall DPC. I didn't even think to check this before reading the CIGA Technical note 14 . This clearly states that if the distance between DPC and ground level is within a brick (as was the case with my property at time of install) then 'numerous other factors' must be assessed before declaring the dwelling as being suitable for CWI. CIGA  Technical note 14 . One of the factors is the relative level of the inner and outer leaf DPC. This is exactly what I found in my property. Ive used a floorboard to show the position of the internal floor. The DPC is clearly a brick below the floorboard and less than brick above the block paving. External leaf DPC is 1 brick below the floor level.
Read more