Perilite required

The materials list calls for a 4 cubic foot bag of perilite or vermiculite. The only place I see it used for is the void under the oven floor, which I measure to be approximately 1.5 cubic feet. Do we need the extra somewhere that I am missing?

I used vermiculite and i used less than one bag. It does condense when mixed with water and cement, but not that much.

Welcome to the BrickWood forums!

You probably won’t use the whole package. I purchased two 2 cubic foot bags and broke into the second one, but most of the second bag is now happily conditioning the soil in my wife’s garden.

It’s a matter of economy; you’d buy many of the small bags and pay a hefty amount, or purchase a single large bag for about $25 and use the surplus in other helpful ways.

By the way, a pro tip: use Perlite if you can get it. It will speed up cure time by about 4 days over Vermiculite. Search these forums for several helpful articles on the topic.

Good luck with your build!

Thanks for the help. Locally I can not find a supplier for larger bags of perilite. Most are gardening centres that stock small 9 litre bags ( about 1/3 cubic foot) hence the question. 4 cubic feet is a lot of bags at $6 or $7 per bag.
Thanks again.

Here is the main post on Perlite & Vermiculite that you should read. In that post you’ll find a link to — they will sell and ship Vermiculite to your door. You can also try Their garden centers stock it for about US$17/2 cu.ft. bag. Their web site will tell you which stores have it in stock.

(I’m guessing by your spelling of “centre” that you may be located in Canada. If that’s true, I apologize for the US-centric supply information. I would expect, though, that since both of these companies also operate in Canada they would both be able to supply you.)