Finding Vermiculite

[sugarsand]

I"m rebuilding a raised flue 4x12 evaporator and plan to use Vermiculite to make the ramp and fill the bottom. Where do I look for this stuff, and is it safe to use? From what I was reading, at one time it contained high levels of Asbestus. How much would I need? I plan to lay ceramic board over the top. Looking for some help or ideas.

sugarsand

[Dennis H.]

I used a brand name Zonalite, it is the same as vermiculite just by another company. It is safe stuff, I would use a dust mask when pouring though. I believe I heard somewhere that it is made from a by-product of steel making, not sure.

I picked up my Zonalite at a construction supply warehouse, Tri-Boro. They sell all sorts of construction stuff. Concrete forms, rebar, reinforcment wire. This is not the average homeowner supply place.

In the construction field they use this stuff as an insulation in concrete block walls and around flues liners in chimneys. So you may be able to look around at places that sell concrete block.

This is the same stuff that is also used in potting soil mix, but it has been treated to not absorbe water, unlike the vermiculite in potting soil. And it is alot cheaper than at home and garden centers.

I picked up a bag of Zonalite that contained 4cuft for about $14.

[OldManMaple]

Sugarsand,
Google "Thermix Chimney Insulation" You can make this yourself as it is a 6 to 1 mix of block fill vermiculite/ portland cement. Smaller bags are available from New England Chimney Supply under their name.

[stoweski]

If vermiculite is vermiculite then Agway carries it. Wouldn't be surprised if TSC also has it. Not sure if vermiculite for plants is the same as vermiculite for heat though. Ie. is it treated with anything?

[sugarsand]

I appreciate the help, thanks.

sugarsand

[lastwoodsman]

Menards has it as well.

Woodsman

[brookledge]

I've bought it at mason supply stores
Keith

[KenWP]

I"m rebuilding a raised flue 4x12 evaporator and plan to use Vermiculite to make the ramp and fill the bottom. Where do I look for this stuff, and is it safe to use? From what I was reading, at one time it contained high levels of Asbestus. How much would I need? I plan to lay ceramic board over the top. Looking for some help or ideas.

sugarsand
Vermiculite hasn't contained asbestos since 1990 so any new stuff is safe. It's puffed rock made with heat. I buy it in big bags to add to soil in the greenhouse.The garden stuff really absorbs water and takes forever to dry out again.

[maple flats]

Try a commercial greenhouse supply, such as Milikowski. They have several outlets across New England. There you will get the best price. Zonolite is vermiculite mixed with styrofoam beads, not good. Vermiculite is made from the slag off steel processing kilns and is popped like popcorn (only at a very high temperature.. It will not burn and has no asbestos in it. If you buy from the greenhouse supply the price will be a small fraction of what you would pay buying small bags from Lowes or TSC or similar. When I bought I first priced Lowes and it would have cost me $500 to do my 3x8 raised flue arch. From Milikowski I only paid just over $100. You can use either large or small curd. The bags will be about 4 CF each if I remember right. Just Google Milikowski.

[KenWP]

Try a commercial greenhouse supply, such as Milikowski. They have several outlets across New England. There you will get the best price. Zonolite is vermiculite mixed with styrofoam beads, not good. Vermiculite is made from the slag off steel processing kilns and is popped like popcorn (only at a very high temperature.. It will not burn and has no asbestos in it. If you buy from the greenhouse supply the price will be a small fraction of what you would pay buying small bags from Lowes or TSC or similar. When I bought I first priced Lowes and it would have cost me $500 to do my 3x8 raised flue arch. From Milikowski I only paid just over $100. You can use either large or small curd. The bags will be about 4 CF each if I remember right. Just Google Milikowski.

Would love to know where you got the info vermiculite comes from the slag in a steel mill.They made it near where I grew up and there was no steel withing 4000 miles.

[Dennis H.]

Mapleflats are you sure about the Zonalite thing having foam beads?? The stuff that I got is called Zonalite and it does not have anything mixed in with it. Just straight vermiculite looking stuff. It reads right on the bag that it is not to be used for mixing with soil as it has been treated to resist absorbtion of water.

KenW I have also heard that vermiculite was made from a by-product of making steel. I can't remember where I heard it.

[CBOYER]

Would love to know where you got the info vermiculite comes from the slag in a steel mill.They made it near where I grew up and there was no steel withing 4000 miles.

Vermiculite is used in electric arc steel smelting as additive in slag to absorb sulfur and phosphorus to get better steels. slag dont produce vermiculite, it eat it:lol:

[DrTimPerkins]

Vermiculite is used in electric arc steel smelting as additive in slag to absorb sulfur and phosphorus to get better steels. slag dont produce vermiculite, it eat it:lol:

Vermiculite is essentially weathered sheets of different forms of the mineral "mica" and is a mined product. Mica, vermiculite, and some types of clay particles are structurally and chemically very similar, just different in size (mica biggest, clay smallest, vermiculite in between). It doesn't look like what we recognize as vermiculite when it comes from the ground. The thin sheets are naturally slightly hydrated (have a little water between them). In the process of making what we call vermiculite, it is treated with heat to a fairly high temperature. Doing so expands the space between the sheets by 3-8x its size, making it fairly light and puffy. It is kind of like puffed wheat or popcorn...just don't try to eat it.

Vermiculite, and a related product perlite, are used in many ways, primarily in horticulture (added to potting mix for aeration and to hold some moisture), is used as insulation (sometimes after being chemically treated to reduce water absorption) in home construction and in boilers (and evaporators), and is used in the steel making process. In the latter case, as already stated, it is used in the smelting process, not produced by it.

If you have vermiculite insulation in your house from prior to 1990, you shouldn't disturb it. It most likely contains asbestos (70% of the vermiculite distributed in the U.S. came from one source, and it contained asbestos). It is fine as long as you don't go up into your attic a lot and disturb it so that small particles make it back down into the living space.

P.S. One of my first Bachelors degrees was in geology.

[Dennis H.]

Now that makes sense. I googled vermiculite and found the same info. A naturally occuring clay type thing that when heated forms vermculite. It sounds like it found mostly in other parts of the world. South Africa, Brazil, China, Russia.

I guess where ever I heard about it coming from a by product of steel making got a little crossed in translation. By-product of steel making, used in steel making. I can how it happens.

Now boys and girls our science class is done for the day, you all may now go home.:D

[maple flats]

I'll believe DR Perkins. I must have been given some faulty info. I stand corrected. Sorry. I do not remember where I got the info originally but it was a long time ago. Must be whoever told me that was confusing the use of vermiculite in removing slag.