There are lots of barbeques on the market ranging from simple trays that hold coals to giant gas-powered behemoths. I am somebody who doesn’t believe in using gas to cook barbequed food, even if you do run it through volcanic rocks you are still not going to get that proper smokey BBQ taste. That is why you need a barbeque that is functional and also cooks the food correctly.
When it comes to building your own BBQ I would suggest that you decide on what materials to use, some may try and find metal containers, but I am a stickler for temperature control so I like to build lots of layers, that allow for temperature control so that I can have trays on about 5 levels, the closest to the coals the hottest and the furthest away is the coolest. The easiest way to build a BBQ like this is to use bricks. A brick BBQ can be built from the ground, ideally on a level surface like concrete and is entirely customisable in how high and wide you would like it. Make sure the width is as wide as the trays and racks available to you, you will need to rest these on bricks that stick out of certain levels. You can choose which levels and how many.
You want to make sure that you put your BBQ on something flat, creating a concrete foundation could be sensible especially if you want to build your BBQ on grass. Also, do not put your barbeque close to a wooden fence or wooden traditional shiplap cladding or you may see them go up in smoke when you’ve got the BBQ lit!