This particular photo was taken with a wide angle lens, so the actual depth of the mantel and fireplace is actually deeper than it looks. The full depth is 21". If you haven't already, I'd recommend looking at electric fireplace models. They have come a long way in function and style, and require less room for installation - make sure you look at models from a fireplace and mantel retailer, as the quality, fit and finish will be far superior as compared to what you'd find at a big box store.