One more (ta in advance and all that)

I have to render the inside of a fireplace, in order that a wood/coal
burning iron stove can go in later.

What would be the recommended mix for that? Something with lime maybe?

On an aside - I'd like to "paint" it white. Paint's not going to like the
heat - so I thought of whitewash/distemper - basically something white,
paintable and lime based. Is that something I could make starting with a
bag of lime? Google's not being helpful with regard to just
buying "whitewash" and "distemper" is more of a doggie disease(!)

Nearest I could find was this:

http://www.wow-wow.co.uk/shop/eco-bu...ash-paint.htma

Are whitewash, limewash and distemper all the same thing?

Ta

Tim