This gas fireplace is direct vented, which means it has a fixed glass front, which seals off the gas burner and combustion firebox from your home. 100% of the combustion air used by the fireplace comes from outside the home through a coaxial pipe. A smaller pipe inside the larger pipe eliminates all combustible gases, maintaining indoor air quality. The vent can be run horizontally through an outside wall, or vertically through the roof. The cost includes firebox opening (single for low-end, back-to-back for the higher-end), and a small-to-large hearth area with wall facings associated with the fireplace.