This is one of the best things you can do for your smoker. I picked up 20 fire bricks at the True Value Hardware store for under $20.00 and only used 17 of them to line the bottom of the barrel. Keep in mind these are not your standard construction bricks. These babies will with-stand a few thousand degrees. They help in two ways. One, they'll make the bottom of your barral last forever. Two, they help stop heat loss out the bottom of the barrel.