Insulating brick smoker

saulgoodbbq said:

Just getting started on a brick smoker trying to decide what to slug the walls with to insulate them for smoking all yr round any advice I got 6 inch cynder blocks for the walls fire brick for fire box trying to get everything here b4 I start thanks for any advice

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Good evening.    There are a couple different things you can use, but....   your firebrick will hold your heat.

I used regular fiberglass insulation between the oven  and block.   On a 10-12 hrs smoke, the only thing that gets warm is around the doors.   Another option is you can fill the void with vermiculite.  It is a masonry insulation.  You simply pour it in.   I used it over the dome of my brick oven.   

Either one, you need to keep it dry till its sealed in.    Of course if you use fiberglass,  you'll want to take the paper off it.   

saulgoodbbq said:

Thank you I was planing to buld of set smoker and someone said if I mix perlite with Portland cement to slug the walls I could use it in the winter do I need fire brick inside smoke chamber. I plaNed on 6 inch block and not sure outside of that yet

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It kinda depends on how much you want to spend.   I'm a huge fan of firebrick.  Their dense and hold heat very well.  They don't obsorb moisture.  Block are very porious and moisture loves them.   You have to drive the moisture out of the oven before it will heat up.   If you have the room and can afford it,  I would line the firebox and oven with firebrick.   In the picture you can see how I stepped mine out.   I took it all up at once.  Not easy, but it worked for me.   If you do firebrick, insulation, block, you wouldn't really need an outside layer.  Even on a 12 hrs smoke, my outside isn't even warm.   The outside layer is just for decoration.   But, you have to make sure everything is sealed from the weather.  If you don't lay a face brick layer,  I would stucco  the block just so the rain would run off better and not soak in as badly.  

You can use your smoker in the winter no matter what you do.  Stuccoing the wall would have no benifit.    Perlite or vermiculite ( same thing, one is ground finer) is a great insulator.    

Love my smoker.   I've fired it at -10F.  It takes about an hour to get to temp, but once there,  its just like another day.   Weather isn't an issue.

Keep us posted.   Once you get started, start a thread for others to learn from.

To keep it all the same, I used type S mortar for my complete build for a smoker.   For my smoker I also used type S.  I mixed it 1 part type S to 2 parts sand.   A very strong mix.     

I used the same mix for the firebrick.  But, I kept my joints to 1/4in. max.   A smoker doesn't get hot enough to burn out the joint, even in the firebox.  I did use fireclay in my brick oven simply because it reaches temps of 800-1000F.   A smoker firebox might reach 300F.   Fireclay isn't needed unless you just want to use it.  If you feel its needed, by all means use it.  Its cheap and easy to use.

Looking forward to this build.  Keep us posted!!

Definitely glue all the firebricks, if you don't need a lot you can buy furnace mortar in tubs. It costs a bit but works great.