You don't need firebrick but it is a better idea. The CMU's do not take heat as well and the joints will fail sooner. I like Sketch-up as a rapid volume prototyping software.
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"perhaps...but then again...maybe not..."
careful there son, those ribs are boiling hot...
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(='.'=) Here there be bunnies...
(")_(")ooo
Pacific Rim BBQ
Bob's Brew and Que
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