Vermiculite and Perlite Blend?

[dtontarski]

Has anyone seen this particular blend of vermiculite attic insulation?

Could this be a blend of vermiculite and perlite?

Or is perlite less spherical?

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[Chad Fabry]

Looks like vermiculite potting soil mix with expanded polystyrene added to further help prevent compaction.

[dtontarski]

Anyone know if Zonolite was ever mixed with polystyrene beads by Grace?

I saw this mix at a prelisting inspection and the owner asked me if I thought it was Zonolite. All of the images I have been able to find online for Zonolite appear to be straight vermiculite.

I see where a vermiculite poystyrene blend was used for both soil enhancement and as cmu insulator, but I haven't been able to find any information online regarding a blend sold as an attic insulator.

This home was in a farming area...perhaps the owner had some of this product left over from his garlic patch and improvised.

[Chad Fabry]

Isn't expanded polystyrene awfully combustible?

[Tom Raymond]

That's ok, there's enough asbestos in the vermiculite to compensate[:-bigeyes

Tom

[dtontarski]

Good question and a legitimate concern - I pulled this off the internet:

How does EPS behave in case of fire?

Like practically all organic building materials polystyrene foam is combustible.

However in practice its burning behaviour depends on the conditions under which it is used, as well as the inherent properties of the material.

These inherent properties differ depending on whether the cellular material is made from EPS with or without a fire retardant additive.

The bonding of other materials to cellular polystyrene also considerably affects its burning behaviour.

When installed correctly, expanded polystyrene products do not present an increased fire hazard.

It is strongly recommended that expanded polystyrene should always be protected by a facing material.

See more at: http://www.eumeps.org/faq.htm

So - if the current owner, or a future owner was to have this vermiculite polystyrene bead mix covered over professionally with another layer of appropriate insulation, this should lower the (potential) fire risk and help to keep any friable asbestos fibers from being disturbed.

I haven't completed this report yet. My plan is warn the current owner not to disturb this and to expect that he may encounter some concerns about this when the buyer's inspector observes it.

I'll also provide them links to several of the websites recommended in previous posts on what to do if you have vermiculite insulation in your home.