Perlite - Is this right? Tools, Tips and Techniques Discuss Perlite - Is this right? in the Pizza Oven Design and Installation forums; This stuff seems way to loose to ever really form a solid bond.. does it look right? I packed it ...

[blacknoir]

This stuff seems way to loose to ever really form a solid bond.. does it look right? I packed it around the flue and it's somewhat hard but I thought it would be a bit more sticky or pourable?

[Neil2]

Looks about right.

Start misting it lightly after a couple of ours and try to keep it out of the direct sun. Keep it damp for at least 6 days.

[trialbyfire]

I was able to find vermiculite at a local nursery but it was really expensive and very small quantity. I ordered 4 bags online from U-Line (the packing company) they were 4 cu. ft each and the total cost was only $135.00 and shipped to me in two days. To my knowledge Perlite and vermiculite are pretty much the same thing. Both used as soil conditioners and when shipping liquids as a absorbent

[texassourdough]

I got mine from U-line as well. Works fine. The markup on the nursery stuff is obscene!

[UnConundrum]

Geez guys. I went to a local brick and flagstone place and got vermiculite for $13.80/bag! You should shop around a bit more.

[texassourdough]

You did good! For some reason vermiculite and perlite can be really hard to get down here. Probably has something to do with winter temperatures and chimney construction. When I built mine five years ago none of the nursery wholesalers or local masonary resources carried it. It was a bit of a bummer!

[karl]

This stuff seems way to loose to ever really form a solid bond.. does it look right? I packed it around the flue and it's somewhat hard but I thought it would be a bit more sticky or pourable?

You are very right. It will never form a solid bound. It is only suitable under compression loads and should only be used as an insulating support layer under the floor fire bricks.

regards from Karl

[DimTex]

for what its worth I found big bags (4 cu. ft.) of perlite at about $20 a bag at a hydroponics store. they also had vermiculite but I liked the coarser perlite better.

[Likeithot]

Thats the stuff alright. I have tried both perlite and vermiculite and I prefer the perlite. In (Tasmania) Australia you can buy it for $32 a 5kg bag (about 10 and a half pounds). Its light stuff for the volume you get, so it cames in a bag that is half the size of a normal car trunk (boot we call in in Australia). Best to be bought from an agricultural supplies place as its used in potting mix. When I use insulation, I mix it with sand and lime. It becomes hard but is still an excellent insulator and you can still build on it. It will compress slightly but you can take that into account.