Brick

[tonka]

I was thinking about doing a fire pit/box in cinder brick, if I line the inside of it with fire brick will the cinder brick still crack or will they hold together good?

[TedA]

Last spring, I used cement blocks for the frame and lined the fire box with fire brick. For the chimney, I used chimney blocks (with square hole in center). At the start of the chimney, I used an 18 inch ceramic/tile (the kind they line chimneys with). The firebox worked fine but my cobbled together chimney barely took the heat. I managed 12 cooks over nearly 4 weeks but the chimney liner cracked in multiple places as did the chimney blocks. However, the mass of the chimney was enough to hold it together. When I took it apart at the end of the season, the liner came out in 8-10 pieces and the chimney blocks in 2-3 pieces. Moving on to a more sophisticated setup in 2014 but it was learning experience.

[psparr]

You could use h vac duct for the chimney. Will last a couple seasons and only costs about $5.

[wrushton]

If you use concrete block ( cinder block) you cant not have a big heat change or wheather change. Line it with a clay brick or a fire brick but make sure you leave a air space so the brick can expand 1" to 2" should work concrete hates heat well the stone in it expands (blow up) we also used sand between the brick an block to take the heat in some jobs.