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Installing a Therma-Tru Pre-Hung Door

Bob is joined by Michael McDevitt of Therma-Tru Doors as Wes Lohr and his crew prepare for the installation of the pre-hung exterior door. Lohr has created a lead pan at the entry that laps up the sides and down the front of the opening and is then covered in silicon to make a weatherproof seal with the door assembly. The door itself has pressure-molded fiberglass skins with raised panels on the interior and exterior faces. These skins sit over a high-density polyurethane core with wood blocks at the lock set, sides, top, and bottom of the door for custom fitting and improved strength. The door is pre-hung and secured to keep it square until installed. To properly install a pre-hung door, the door assembly must be screwed into the jamb, not the casing, since only the jamb is structural and can prevent the door from sagging. Lohr and his crew tack the door into the opening, check it for square, then open it and screw it into place, through the jambs. Therma-Tru leaves two pre-drilled screw holes at the top of the door to screw it into the top jamb and prevent the door from sagging in. Once in place, the door only needs one coat of latex paint. More information