Permanent Cinderblock Pit

95% of this pit was designed by another Brethren (the name escapes me right now) but this is my version. Hope this helps:

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.

Firebrick or any flat masonry material would work. I also got the idea from another site to line the top interior firebricks et al with scalloped concrete edging.



Which you then lay your rebar and expanded steel grate on and it fits snug. Depending how long you want your pit to last, you can leave the "cinders" empty, fill with sand, or concrete.

Brizz had a great design. Istaed of fire bricks, you could pour the cinders full of sand. Now that's thermal mass.

Take a look at these.
http://www.ibiblio.org/lineback/bbq/pits.htm

There is nothing permanent about a cinder block pit.

You line the pit to prevent the effects of thermal expansion and contraction from damaging the pit over time. This is true for any pit, but, particularly for pits made from modules (such as brick or CMU's). The expansion and contraction of unlike materials will force the joints to fail. The use of un-mortared fire bricks (or other such dense material) will absorb enough heat to prevent the failure fo the external (more permanent) pit walls.

If you build from true clay brick, there is a small benefit to the use of the denser red brick, plus, it major league looks better. But, the benefit has a significant cost in dollars spent, and there is no benefit to poorly built brick, it will fail quickly.

Calculate the number of CMU blocks you would use, then figure out the volume of the cells, if you are going to fill each cell, you can easily figure that volume. It will be more than you think. I leave you to the math. :tongue:

A nice addition to this design would be a fire pit on the side. I used a CB pit for many years, mine was not mortared but was very close to this size and I had a fire pit on the side with an open front.

One this size is so versitle, whole hogs to chicken thighs.