Before talking about the design, you first have to determine the type of fireplace you want to install. Is this going to be a real wood burning fireplace? (do you have the permits?) Or is this going to be a subtle gas burning imitation fireplace? There are other options as well such as pellet burning fireplaces, so you need to look around and scope out the costs before settling in on the fireplace designs you wish to implement. After you’ve selected the type of fireplace, you need to begin the design phase. This starts with an assessment of the space and room you have to operate within. If you have a huge and open space, you may wish to go with a large brick encased fireplace, but if you’re tight on space you will have to keep things simple and just focus on its style and presence without worrying so much about its physical size.