What to Know Before Replacing an Exterior Door
Fit, weather sealing, brick mold, and threshold — the details that separate a real install from a cosmetic swap.
Replacing an exterior door is one of those projects that looks simple until you actually pull the old one out. Here is what actually matters.
Rough opening and squareness. Older Texas homes settle. The rough opening is rarely perfectly square, and a new pre-hung door will not swing correctly if it is not shimmed and set right. This is where most bad installs go wrong.
Threshold and sill. The threshold is what stops water. If it is not sealed to the floor and to the door jamb properly, water finds its way in. On exterior doors this leads to rot on the sill plate and to soft spots on interior flooring.
Brick mold and exterior trim. The exterior trim around the door — brick mold on brick homes, casing on siding homes — carries most of the weather load. Old brick mold usually needs to be replaced when a door is replaced. Caulking it back over the old rotten piece is a shortcut you will see fail within a year.
Weather stripping and sweep. New doors come with weather stripping but they need to be adjusted so they compress evenly around the frame. The sweep at the bottom needs to actually touch the threshold. This is finish work that gets skipped on rushed jobs.
Locks, strike plates, and hinges. A door that closes but does not latch cleanly is a security and comfort issue. Strike plates need to be shimmed and aligned. Hinges need to be set flush. Cheap installs skip this step.
Interior side finish. Once the door is in, there is casing, caulking, and paint or stain to complete. A good install leaves the interior side ready to paint. A bad one leaves visible gaps between the jamb and the drywall.
When you are getting an estimate for a door replacement, ask what happens with the brick mold, what happens with the threshold seal, and what the finished interior side will look like. That conversation tells you whether you are getting a real install or a cosmetic swap.