making a pad for a rocket heater

Byrdi and ant in sea town here.
we have an chimney that old oil furnace wuz conected to.
we took out cabinet now want to rocket heat there.
we plaan to reenforce floor then what does one do to create pad for the rocket.
would a cob slab on the wood floor be the way?
what do people build thier rocket heaters on when you aern't cool enough to live ina cob.
Also, how to treat walls around chimney?
If sum kind soul could tell us how other wood floor rocket cob treatments went down this would help us for we are really amped to git the rocket ball a rollin.
Byrdi and ant

        There are types of concrete made with vermiculite and perlite. They are better insulators than more solid materials and they are not flammable. The companies that make aerated concrete may have some idea of appropriate R-value for this purpose and how to achieve it. Talk to someone who sells woodstoves since they regularly protect wooden floors from extreme heat.

hey all!
do you have to use masonry perlite for rocket slab ,on wood floor situation?
Or does the horticulture perlite do da trick.
It makes sense for the heat vriser insulation to be masonry perlite,or can u just use horticulture perlite.
cheers .