Symptoms
- Visible gap or light under the closed door
- Cold air noticeably comes in near the floor
- Door sweep looks worn, torn, or missing
Likely causes
- CommonWorn or missing door sweepThe rubber or brush strip on the bottom of the door wears down over years of dragging across the threshold.
- CommonThreshold not adjusted to meet the door properlyMany exterior thresholds have adjustment screws that can be raised to close the gap.
- PossibleDoor sagging on its hinges, raising the bottom edgeA sagging door changes the gap size at the bottom even if the sweep itself is fine.
- PossibleThreshold worn down or settled over timeWood or metal thresholds can wear or shift with years of foot traffic and settling.
What to do
- Close the door and check for daylight or airflow along the entire bottom edge.
- Look for small adjustment screws along the threshold and turn them to raise the threshold slightly to meet the door.
- If no adjustment screws exist or the sweep is worn, remove and replace the door sweep with a new one cut to fit the door's width.
- Check hinges for looseness that might be causing the door to sag and creating an uneven gap.
- Test the door's swing and closing force after adjustment to ensure it doesn't drag or bind on the threshold.
- Recheck for drafts on a windy day after making adjustments.
Tools and parts
- Screwdriver
- Hacksaw (to cut a sweep to size)
- Tape measure
Adjustable door sweepSearch: “adjustable door sweep for exterior door”
When to call a pro
Call a door installer if the threshold itself is damaged or badly worn and needs full replacement rather than adjustment.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.