Identify my Insulation

[Brains]

Anyone in the building trade in the early 1970's ??
Can you identify what this insulation is made from in the attic of an ex council house built about 1973 in SE London

It looks like gravel
It has the consistency of dried porridge oats
It's very light
Some of the flakes seem to be silica based (as you get rainbow colours in direct light)
It has white wooly bits mixed in with it (which may be from a later covering ?)

 

[Randomnerd]

That may well be vermiculite flakes. Could contain asbestos. Take extreme caution and a professional eye

 

[gbb]

I don't know what it's called but I remember it being used.

 

[bikingdad90]

It’ll be some sort of loose fill insulation like this from vermiculite. If it’s ex council good chance it contains asbestos! Stay well clear and get an expert in to clear it out and then lay 270mm plus of new rockwool type. You’ve only got 170mm there. It should have another layer covering the joists.

https://shop.vitcas.com/vermiculite...MIztGq7LK87QIVdIBQBh3i7QSkEAQYASABEgLhvvD_BwE

 

[Archie_tect]

Never seen that before but then there were lots of 'new' products being trialled in the 70s!

@bikingdad90, I specify 450mm [3 layers of 150 each layer cross laid] which passes building regs now !
Ideally use Earthwool- cheaper than Rockwool and has a better overall U-value.

 

[bikingdad90]

Never seen that before but then there were lots of 'new' products being trialled in the 70s!

@bikingdad90, I specify 450mm [3 layers of 150 each layer cross laid] which passes building regs now !
Ideally use Earthwool- cheaper than Rockwool and has a better overall U-value.

While the insulation is up it’s a good opportunity to lay joists running parallel to what’s there already which are a minimum of 300mm deep so you can put board on top without flattening the insulation and loosing some of its thermal properties. Also worth looking at the loft hatch opening and getting rid of any gaps as that is often a source for entrance of fibres into the house. Also depending on location could be a good opportunity to move access to a sensible location not in a bedroom or on the stairs.

You could also qualify for a green homes grant towards the cost of the work.

 

[Cycleops]

Remember that well. It was called I think ‘Mica Fill’ or something very similar including the word ‘Mica’. I think it was made from granules of expanded polystyrene, the stuff that fridges and like products come packed in. Don’t think there were any dangerous ingredients.

Edit: it was Micafil, you can still buy it, read about it here:
https://www.thegreenage.co.uk/micafil-loose-fill-loft-insulation/
Made from Vermiculite, a naturally occurring mineral.

 

[Dayvo]

We had something like that in our loft when I was a kid (mid/late 60s).

When it became common knowledge that asbestos was dangerous my dad had it removed and that yellowy wool insulation was put down.

 

[Brains]

Thanks all, it looks like its a Vermiculite based product.
Which is still sold as loft insulation today under the name "Mikafil"

The question appears to be, was it laid before 1978?
The pre 1978 Vermiculite could contain a small percentage of Asbestos if sold as "Zonolite",
IF (big IF) is came from one mine in the USA who were a major global supplier of the stuff from 1920 to 1978.
Depending on who you believe, it's either 100% definite, or highly unlikely.

I'm going to knock on a few doors later in the week and see if others have the same stuff in their lofts, if they do, then it was laid when the house was built in 1973, if not, then it was probably laid when insulating attics became a thing to do in the mid 1990's (and after the great council house sell off of the 1980's)

 

[bikingdad90]

When the council house sell off happened to housing associations under local authority stock transfer arrangements then most entered into an agreement to renovate the properties and most of these agreements included removal of and management of asbestos as an element of the works

 

[Cycleops]

If this was installed by the council you can bet that if there any concerns about the safely of this product they would have had it removed.

 

[Globalti]

Yes vermiculite, used until quite recently to pack parcels if you really wanted to annoy your customer.

My Dad filled our attic with that stuff in about 1965

 

[Brains]

When the council house sell off happened to housing associations under local authority stock transfer arrangements then most entered into an agreement to renovate the properties and most of these agreements included removal of and management of asbestos as an element of the works

We know from when we renovated the property in 2007 that asbestos panels were used in places like the tops of doors and cupboard walls. (And are still there today, covered in a thick layer of paint, so as long as they are not disturbed, they are safe)

So if the Council did give a damn about their properties (they still own the majority of properties on the estate) I know they all contain some asbestos, so I have no faith they would have removed the Vermiculite in 1978 when the asbestos problems became known.