A door that scrapes at the bottom while showing a gap at the top is a classic geometry problem. The bottom edge reaches the frame or floor before the top edge can seat against the stop. This misalignment usually comes from a racked frame, a twisted slab, worn hinges, or a floor that is not level.
The good news is that the problem can be solved without guessing. The key is to diagnose the door opening as a three-dimensional system before cutting or planing anything.
What “Bottom of Door Hits Before Top” Really Means
When a door closes, the latch edge should meet the strike jamb evenly from top to bottom. If the bottom corner hits first, the door is entering the opening at an angle. The top corner then remains shy of the stop, creating a visible gap or a light leak.
The contact may be against the floor, threshold, or strike jamb. Each point tells a different story. A floor strike points to a hump, sag, or swollen bottom edge. A jamb strike points to a frame or hinge problem.
Homeowners often assume the door slab is crooked. In many cases, the slab is square, but the opening is a parallelogram. The door is simply following the shape of a racked frame.
The Most Common Causes of Bottom-First Door Contact
A Racked Door Frame
A door frame can go out of square when a house settles, a foundation shifts, or a header sags. The hinge jamb and strike jamb may both be plumb, yet the head is not level. This creates a diagonal opening that forces the bottom of the door to lead.
Exterior doors are especially vulnerable. A swollen sill, rotted threshold, or heaved porch slab can push the frame out of alignment. Moisture management around the opening matters as much as the door hardware.
A Twisted or Warped Door Slab
Wood doors can twist when one side absorbs more moisture than the other. The bottom may cup outward while the top stays flat. A twisted slab will often hit at one bottom corner and show an uneven gap at the opposite top corner.
Solid wood and engineered doors react differently. A hollow-core door may warp from a leak or high humidity. An exterior door may delaminate at the bottom after repeated wetting.
Hinge Problems and Sag
Loose hinge screws, stripped holes, or worn hinges let the door drop. The top hinge often carries the most weight, so it fails first. When the top hinge pulls away, the latch edge can tilt and the bottom can drag.
Hinges must also be aligned. If one hinge leaf sits deeper in its mortise than the others, the hinge axis is not straight. That small difference changes how the door swings into the frame.
The 10-Minute Diagnosis: Plumb, Square, Twist, and Swing
Before reaching for a plane, test the opening. A few minutes with basic tools will prevent irreversible cuts. The goal is to find whether the problem is the frame, the door, the hinges, or the floor.
Check the Frame for Plumb and Square
Place a 4-foot level against the hinge jamb. Check it in both directions. Repeat on the strike jamb. If either jamb leans, the door will swing into a tilted opening.
Measure the opening diagonally from top hinge corner to bottom strike corner. Then measure the opposite diagonal. A difference of more than 1/8 inch over a standard door height suggests a racked frame.
Check the Door Slab for Twist
Remove the door and lay it on sawhorses if possible. Sight along the bottom edge and top edge. A twisted door will rock on two opposite corners instead of sitting flat.
Another test is to place a straightedge across the door face at the top and bottom. Gaps that switch sides indicate twist. A severely twisted exterior door is usually a replacement candidate.
Check the Hinge Axis and Screws
Open the door and wiggle it gently. Movement at a hinge means loose screws or a worn hinge. Tighten every screw, then replace any that spin freely with longer screws that reach the framing.
Inspect the hinge mortises. The leaves should sit flush and parallel. If one hinge is recessed too deep, the door can bind or angle. A screen door that slams in the last few inches often shares this same hinge-axis misalignment, as covered in this screen door slam fix guide.
Check the Floor and Threshold
Run a straightedge along the floor where the door swings. A hump, dip, or sloped threshold can make the bottom edge contact early. Mark the exact contact point with painter’s tape.
Close the door slowly and watch the gap. If the bottom hits the floor while the top has a gap, the issue is vertical. If the bottom hits the strike jamb while the top has a gap, the issue is angular.
The Hidden Geometry: Why Small Hinge Changes Move the Latch Edge
A door is a lever. A 1/8-inch adjustment at the hinge can become a 3/8-inch change at the latch. This is why a tiny shim behind a hinge can solve a large-looking gap.
Shimming a top hinge changes the tilt of the door. Moving the top of the door toward the strike jamb can close a top gap. Moving the bottom away from the strike jamb can delay bottom contact.
Adjust one hinge at a time and test the swing. Stacking multiple shims without a plan can create new binds. The best result comes from small, measured changes.
Fix #1: Tighten, Rebuild, and Shim the Hinges
Start with the hinge system because it is the least destructive repair. Remove one hinge at a time and inspect the screws. Replace short factory screws with 2-1/2-inch or 3-inch screws in the top hinge.
Long screws can pull the jamb toward the framing and lift a sagging door. Do not overtighten, because the jamb can crack. If a screw hits a wire or pipe, stop and use a different hole.
For stripped holes, remove the screw and inject wood glue into the hole. Tap in a wooden golf tee or dowel, let it dry, then cut it flush. Re-drill a pilot hole and reinstall the screw.
If the door needs a hinge shim, cut a piece of cardstock or plastic to fit behind the hinge leaf. Add one thin shim, close the door, and check the gap. Continue only if the bottom-first contact improves.
Fix #2: Correct a Racked Door Frame
If the frame is out of square, hinge adjustments may only be a temporary patch. Remove the interior casing to expose the shims and framing. Check the jack stud and header with a level.
Shim the low side of the header or the loose jack stud until the opening is square. Secure the shims with construction adhesive and nails or screws. Reinstall the casing after the door swings correctly.
Exterior frames may need the threshold and sill checked first. A rotted sill can let the entire frame settle. If a porch post or deck support has settled, the frame above may rack. The process for restoring a structural post is similar to extending a 6×6 post.
Fix #3: Trim the Door Bottom Only After Diagnosis
Cutting the bottom is the most visible and least reversible fix. Use it only after hinges, frame, and floor have been checked. If the bottom still rubs, remove the door and mark the contact area.
Plane in small increments. A block plane works for minor trimming. A power planer is faster but demands steady control. Cut 1/16 inch at a time and test-fit the door.
Bevel the bottom edge slightly on the latch side. This reduces future catching as the door swings. Always seal the cut edge with primer and paint to stop moisture absorption.
If the door has a sweep or weatherstrip, remove it before cutting. Trim the sweep only after the door fits. A tight sweep can create the illusion of a bottom hit when the door is actually dragging on the seal.
Fix #4: Adjust the Strike Plate and Weatherstripping
A strike plate that sits too far forward can pull the door into the jamb. If the bottom contacts the strike side first, the plate may be misaligned. File the opening slightly or move the plate a small amount.
Weatherstripping can also resist the top of the door. If the top seal is too thick, the door may stop before the bottom clears. Adjust or replace the seal with a lower-profile product.
Do not enlarge the strike plate until the door swings freely. The strike plate should guide the latch, not force the door into an unnatural angle.
Fix #5: Control Moisture and Seasonal Movement
Wood doors swell in humid weather and shrink in dry weather. The bottom edge is closest to damp floors, slabs, and thresholds, so it often swells first. This can create a seasonal bottom-first hit.
Seal all six sides of a wood door, including the top and bottom edges. Use a dehumidifier in damp basements and improve drainage around exterior thresholds. If the door sits near a damp slab or porch edge, moisture can move upward. Review cement board ground contact details for moisture-resistant assemblies.
In winter, dry indoor air can shrink the door and create new gaps. Avoid over-trimming during a dry season, because the door may swell again in summer. Leave a small clearance and use adjustable seals.
Diagnostic Table for a Door That Hits at the Bottom
| Symptom | Likely Cause | Quick Test | Best First Fix |
|---|---|---|---|
| Bottom hits floor; top has gap | Floor hump, swollen bottom, or door sag | Slide straightedge under door | Tighten top hinge; trim bottom last |
| Bottom hits strike jamb first | Racked frame or uneven hinge axis | Measure frame diagonals | Shim hinge or square frame |
| Door drags only in humid months | Moisture swelling | Compare seasonal gap | Seal edges; control humidity |
| Top hinge moves when door is wiggled | Loose or stripped screws | Turn screws by hand | Use long screws or dowel repair |
| Bottom corner rubs; opposite top corner has gap | Twisted door slab | Sight along door edges | Replace severe twist; adjust hinges for minor twist |
Step-by-Step Repair Sequence That Avoids Damage
Follow a fixed order so you do not remove material unnecessarily. Start with the simplest adjustments and move toward permanent repairs. Test the door after every change.
First, tighten or rebuild the hinges. Second, adjust hinge shims to change the door angle. Third, correct the frame if it is out of square. Fourth, trim the bottom only when floor contact remains. Finally, seal and finish the door.
After repairs, wait 48 hours before calling the job complete. Wood and weatherstripping need time to settle. Open and close the door several times during that period.
Common Mistakes to Avoid
One common mistake is planing the bottom before checking the top hinge. A loose top hinge can mimic a crooked door. Fixing the hinge may restore the gap without any cutting.
Another mistake is shimming the wrong hinge. A shim at the bottom hinge changes the bottom reveal, while a top hinge shim changes the top reveal. Adjust one and observe before adding another.
Using very long screws near electrical wires is risky. Door jambs can hide romex or plumbing. If a screw meets unusual resistance, stop and choose a new location.
Ignoring moisture leads to repeat problems. A door that swells every summer will keep hitting unless the bottom edge and surrounding assembly are protected. Painting the cut edge is not optional.
When to Repair vs Replace the Door
Minor twist, loose hinges, and small frame misalignment are repair jobs. A door with severe twist, cracked stiles, or delaminated edges may not be worth saving. Exterior doors that have rotted at the bottom usually need replacement.
If the frame is structurally failing, door replacement alone will not solve the problem. The opening must be made square and stable first. A professional may be needed for foundation, header, or sill repairs.
Prevention for New Door Installations
Install the hinge jamb plumb and the head level. Use shims behind the jamb at every hinge location. Do not rely on the casing to pull the frame into shape.
Leave a consistent 1/8-inch gap around the door and a 1/2-inch to 3/4-inch clearance at the bottom, depending on the floor covering. Seal all sides of the slab before hanging it.
Use three hinges for most exterior and heavy doors. A third hinge reduces sag and keeps the hinge axis straighter. Check screws annually and tighten any that have loosened.
Final Thoughts on Bottom-of-Door Contact
A door that hits at the bottom before the top is a symptom, not a diagnosis. The real cause is usually a small change in the geometry of the frame, hinge, or floor. Finding that change prevents repeated fixes.
Start with the hinge system, test the frame for square, and save trimming for last. With careful measurements and small adjustments, the door can close evenly without scraping or leaving a top gap.