Help me identify this type of insulation

Aug 13, 2005 Last reply: 5 years ago 13 Replies

I have a house that has all exterior walls made from poured concrete, no wood framing at all. The insulation on the interior is something I've never seen before and looks to be actually part of the form to pour the concrete into. It is black in color, very porous yet solid, lightweight, about 2" thick, and crushes very easily - even between two fingers. When it is crushed it turns to a sandy texture and emits a foul odor, kind of like rotten eggs. My first thought was pumice, but this comes in one foot wide by four foot long sheets. The house was built in 1953 so if anyone knows what construction methods were used back then and has any info please let me know. I'm just hoping its not some type of asbestos, or something else that is hazardous.



Thanks, LW


sounds like asphalt board to me. It is available at the box stores in 4x8 sheets. Where I live they use it sometimes between the concrete and the earth back fill.

Concrete wall above grade?

Do you live in a Edison house? Pictures please.

My brother in law founds some insulating pipes one time. he took it back to the shop and had a blast with it. He call it fart rock.

Stretch

It may be the form they poured the walls in. There is a fairly new construction technique where they stack foam blocks with spacers built in them to form the wall, then they pour the center solid.

So do you, or anyone else, know what this stuff is made of? I tried asking all kinds of people what it is and about 95% of them didn't know what I was talking about. Those who did only saw it once, maybe twice, and didn't know what exactly it is made of either. I'm pretty confident it is the form the concrete was poured into and also doubles as insulation. I know it isn't asphalt board as mentioned earlier, and it definately isn't foam used in newer ICFs.

I had a chunk of that stuff when I was a kid. Like pumice or a volcanic black glass and it did stink. Now I know what it was for..Sorry I cant help but I know what you're talking about

ICF's, (Insulating concrete forms) are getting very popular. Makes a very energy efficient house also.

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I beleive what you have is called FOAMGLAS. We have it at the chemical plant that I work at as insulation on our pipes. I just spent the day ripping it off one pipe. It definitely smells like rotten eggs. This is due to the hydrgoen sulfide gas that is contained in the cells. The company that makes it provides a safety data sheet that will inform you of any hazards. It can be found online at the following address.

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Click on the 'FOAMGLAS Insulation (all grades)' link and that will tell you all you want to know.

first get it tested for asbestos, before moving or disturbing it futher......

better safe than sorry.

That sounds like those 'glass sanding' blocks. As they crumble, smells like hydrogen sulfide, too.

What u have is called "foam glass" insulation. Primarily used on chilled water piping insulation. Most commonly known as "fart rock" it is non hazardous and still used today.

Fart rock is what it?s called in the insulation industry it? ?s normally used around steam lines because the odor is the fire retardan t mixed in its perfectly safe by today?s standards

May not be here but this co makes fire retardant insulation:

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We used to break it off pipes in my Middle School that was built in 1953. The principal actually made an announcement one day that no more "fart rocks" were to be harvested from the building.

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