Door advice: exposed perlcrete ok?

[Abouna]

I just poured a door, the front is Ipe, the back 2.5" is 8:1 perlcrete.

Any reason I can't just leave the perlcrete exposed? I had not planned on encasing it. Will it eventually just crumble to nothing?

[david s]

Re: Door advice: exposed perlcrete ok?

I just poured a door, the front is Ipe, the back 2.5" is 8:1 perlcrete.

Any reason I can't just leave the perlcrete exposed? I had not planned on encasing it. Will it eventually just crumble to nothing?

Yes it will, or at least mine did. Generally the better the insulating material is the weaker its strength.

[Abouna]

Re: Door advice: exposed perlcrete ok?

Well. OK then!

- I assume it's safe however to use exposed if I decide to use it as is?
- Any ideas short of some kind of metal shielding to prolong it?

[david s]

Re: Door advice: exposed perlcrete ok?

See how it works and try as much as possible not to use it above baking or roasting temperatures. Portland cement does not like high heat. When it finally cracks or abrades to bits you could try using calcium aluminate cement, which can handle the heat, but when it is mixed with perlite you end up compromising the strength of the stuff. To make it stronger you can try making up the panel then taking it to a local potter and have them fire it for you. But only take it to 1000 C because the perlite fails at 1100 C.
It is probably easier to encase the whole thing in metal.