www.sausagemaking.org

Sorry in advance
have decided not to go the pre built unit ,and to make my own hot smoker have decided on size etc. and will put up photos of build as it goes.
my question is on the inside of unit what would you all use looking around have seen wood ,steel ,even spotted one that used fireproof board is this safe to use
sorry again

It really doesn't matter what you line the inside of your hot smoker with. I prefer steel or stainless sheeting.
Check the fireproof board for chemicals used.
If you decide to use steel, do NOT use galvanised for obvious reasons.
Walls have to be insulated but not with Styrofoam. I have compressed glasswool in mine. Works great.
Good luck with the build.
Cheers,
Jan.

Steel is probably the most economical choice, going stainless is quite a cost adder, and frankly after a month or so of use the inside will be well seasoned and you won't be able to tell whats under the seasoned surface. Just coat the steel with a good coat of veg oil when seasoning it the first time. I also light sand new steel and give it a coat of oil during fabrication. I would not use any wood or board type products, just don't know what they will out gas as they get hot. Use an insulation that is rated at least 100 degrees above your highest cooking temp, for hot smoking that should not be hard to find. Rock wool is a good choice.

Rock wool or maybe Vermiculite depending on the structure, would be interesting to build a brick built, insulated smoking chamber for both hot and cold smoking but as to power consumtion to heat it for hot smoking I have no calculations.
Possibly a vertical oil drum within a brick square with vermiculite in between the drum and bricks, the possibilties are endless but obviously anything with brick build'part brick build would be permanent? position but if you have room it could be a feature in the garden, will be interesting to follow this project.
Regards Gary.

they can't sell Vermiculite over here as its contains asbestos.

What are the highest temps you plan for this smoker? For me my hot smoker (stick burner) runs 225F to 300F and my sausage smoker never higher than 180F. Hot smoker is steel and the other is plywood and pine board with foam insulation. There is a picture of the sausage smoker and the hot smoker can be seen in the background in the 6th post here viewtopic.php?f=13&t=11005

don't think more than 120c but most of the time a lot cooler
have started on the internal steel case