Thermo-Rite's stock Regal and Original fireplace doors install in one of two ways, both being easy for the average homeowner.
Method 1: The enclosure is installed using the lower "L" brackets and the upper pressure clamp & screws. Two holes are drilled into the lower firebox and attached with supplied anchors. The upper "L" brackets are adjusted so they screw up against the lintel bar.
Method 2: Optional side mounting brackets allow the enclosure to be attached by drilling 4 holes and mounting the enclosure using the supplied anchors. In both types of installation the supplied fiberglass insulation is placed behind the enclosure to seal up the installation.