Standard clay bricks cannot be used in fireboxes because they are not able to withstand the temperatures that they would be exposed to. It is important to use a type of brick suitable for the application, even if it is more expensive. Firebrick comes in a variety of colors and can be laid in decorative patterns.
Firebricks cost about $3 to $7 per brick.
Costs vary greatly by region (and even by zip code). To get free estimates from local contractors, please indicate yours.