If your door doesn’t stay in place when you leave it open, sticks when shut, or the doorknob or deadbolt don’t align properly anymore, you may have a sagging door.
A sagging door is often an alignment issue. While this sounds difficult to fix, the process of getting everything lined up again can actually be very simple. In fact, depending on the cause, you might be able to tackle the repair in mere minutes!
These instructions will walk you through steps to correct the issue, starting with the simplest solution.
Tighten the Door Hinges
Over time, screws often come loose. Sometimes this is due to standard use, though the length of the screws can also be a factor.
Begin by opening the door to expose the hinges and tighten the screws that go into the door jamb. Use a screwdriver instead of a drill, so you don’t risk over tightening the screws or stripping the screw holes. If a screw is stripped, replace it with a 3-inch screw for better support. Once those are all tightened, move on to the screws that attach the hinge to the door. If the screw hole is stripped, then additional steps are required.
For solid core doors, remove the screw and replace it with one that is one inch longer than the one that is removed. You may need pre-drill the hole with a 1/8-inch bit to the desired length first. For hollow-core doors, remove the screw and reinforce it. Simply dip a toothpick or wood splinter in the wood glue and use it to fill the screw hole with glue. Then, drive the original screw back into place, cleaning up any excess wood glue that may have been pushed to the surface.
After every screw has been addressed, test the door to see if it still sags. If not, you’re all set. Just leave the door open to help the wood glue dry, and you can return to using your door as usual. If the door still sags, proceed to the next step.
Replace Hinge Screws in the Door Jamb
Open the door to expose the hinge screws as you did before. Now, remove one of the screws that attaches the hinge to the door jamb. Ideally, select the middle screw from the second hinge from the top. This one is centered, so the weight of the door won’t be as likely to shift much when it’s pulled.
If the removed screw is less than 3-inches in length, then it’s wise to replace all of the screws that attach the hinges to the door jamb. 3-inch screws often get enough penetration to reach the framing on the other side of the door jamb. This will provide more support, making it less likely that the door will sag based on how the hinges connect to the door jamb.
Begin replacing the screws one at a time, starting with the three in the hinge located second from the top of the door. Then proceed with replacing the screws on the upper hinge and, finally the lower one. Test the door again to see if the alignment issue still exists. If the door opens and closes properly, you’re done. If not, proceed to step three.
Adjust the Hinge Using Screws
While door hinges aren’t actually adjustable, there is a method for shifting their alignment slightly. Now that you have 3-inch screws in place, you can draw the hinge in to make small adjustments. For example, if your door rubs near the top of the side jamb (the side without the hinges), simply open the door to expose the hinges and tighten the center screw in the upper most hinge another quarter turn. Then, test the door to see if the issue is resolved.
If not, you can repeat this tightening process multiple times as long as gaps don’t begin forming at the door trim joints. However, if you can’t get that next quarter turn, it could be that the jamb is tightly fitted against the framing or shims, so don’t force it.
The same process can be used on different hinges to correct sags in other directions. If the door rubs on the lower portion of the side jamb or head jamb, adjust the bottom hinge instead of the top one. If the door rubs along the entire side jamb, draw in all of the hinges and not just one. Test the door after each quarter turn until the issue is resolved or you can’t do any further tightening. If an alignment problem still exists, proceed to the next step.
Adjust the Hinge Alignment
In some cases, the hinges themselves are causing the problem if the door isn’t operating smoothly or is sagging. Often, you can see this issue by examining the alignment of the hinge knuckles when the door is in the closed position. If the knuckles don’t appear to line up straight, you first need to remove the pin from the hinge. This may require you to force it up by pushing through the open end with a slim, sturdy object, like a nail with the point cut off.
Once removed, look at the top two hinge knuckles to see if they are aligned. If not, grab some pliers and, while only applying light pressure, gently shift the second knuckle until it aligns with the first. To avoid damaging your hinge’s surface, you may want to cover the grabbing surfaces of the pliers with a few layers of masking tape. This helps keep the rough surface from scratching the hinge. After the first two knuckles are aligned, place the hinge pin back into the top to keep them in place. Then examine the third knuckle to see if an adjustment is necessary and continuing downward, always sliding the pin into place as you transition from one knuckle to the next.
Only adjust one hinge at a time so that the door has the proper support, but make sure to test the door after completing each hinge. If your door rubs on the upper portion of the side jamb, it’s possible realigning the top hinge is all that it will take to get things back in order. If the door still sags after all of the hinges have been adjusted, go to the next step.
Draw in the Side Jamb
Another option that uses a similar approach to step three is to adjust the latch-side jamb using screws. Generally, this should only be used if adjusting the hinges didn’t work but can be easier to manage than planing the door.
Start by identifying where the door is rubbing the side jamb, then open the door so you can access. Next, using a countersink bit, create a countersink hole for the screw head near the center of where the door is rubbing against the jamb. Then, take a 3-inch screw and drive it into the door jamb.
This can work by tightening the jamb against the framing, providing more space for the door. Tighten the screw gradually, and test the door often. If the door is no longer sagging, you can stop. Otherwise, tighten the screw further and keep an eye on the trim to make sure joints aren’t opened. Once done, you can cover the screw head with wood putty, and even sand it and stain it to match the door.
Prepare to Plane the Door
In some cases, planing the door is unavoidable. However, it isn’t necessarily difficult if you complete the proper preparations.
Your first step will be scribing the door. Start by placing a strip of masking tape on the door in the area that is contacting the jamb. Next, grab a carpenter’s compass and set it so that the pencil tip and compass point are 1/8-inch apart.
Slowly run the point along the jamb, allowing the pencil to create a line down the masking tape. Once the pencil stops making contact with the surface of the door (because the tip of the pencil falls into the gap), your line is complete.
Next, you’ll need to remove the door. Often, the easiest way to do this is to remove the pins from the hinges and pull the door off that way. Start by placing a shim to support the swinging side of the door. Tap the pins out, beginning with the bottom hinge and moving up, using the blunted nail and gentle taps. Be ready to catch the weight of the door once the last pin is pulled, as it could come loose and fall. Set the hinge pins aside for later. Then, head outside or to your garage or shop and get ready to plane the door.
While the name suggests using a planer is required, a belt sander is often a better tool. Start with 50-grit sand paper and use the pencil line on the masking tape to guide your efforts. Keep the sander moving, so you don’t create any holes or remove more material than originally intended.
When you are about 1/16-inch away from the line, switch over to 80 grit sandpaper and continue. Once you reach the line, change to 120 grit sandpaper to smooth the edge. You may also want to slightly round any sharp edges created by the sanding process at this time, but take care to do the bare minimum necessary to avoid changing the shape of the door or accidentally creating a bevel. Often, just a couple passes will round the edges nicely.
Rehang the Door and Test
Once you’ve finished the planing process, you’ll need to rehang the door to test the fit. Align the hinges (using a shim for support, if necessary), placing the pin in the top hinge first and working your way down. After the pins are in place, test the door to see if the issue is resolved.
In some cases, you may need to sand off additional material to get the right fit. In the end, you want to ensure there is a 1/8-inch gap between the door and the jamb all of the way around. When you achieve the proper gap, you can refinish the sanded edges to match the rest of the door.
Using the steps above, almost any sagging door can be fixed. With any luck, one of the first few will be all you need. If not, this entire process is still accessible to almost any homeowner who is willing to dedicate a little time and attention to the cause.