Whether it’s the result of DIY mistakes or natural movement over time, a sagging internal door is a problem that needs fixing. It can cause a door stick to stick, rub against the frame or fail to latch – which is a nuisance every day, and a potential safety hazard when reliable access is critical.
“Internal doors sag for a handful of reasons, and most of them come down to either the hinges or the building itself,” says Luke Bowes of The Door Company UK.
“Loose or worn hinges and screws are probably the most common culprit – over time they can wear or lose their grip, and the door starts to drop. You’ve also got things like seasonal movement, where timber expands and contracts with changes in humidity, which can gradually throw a door out of alignment.
Article continues below“Older properties especially tend to suffer from general building settlement, where the frame shifts slightly and takes the door with it. And poor installation from the outset is another cause worth mentioning,” he adds.
According to Guy Davies, Owner of GLD Joinery, many of the problems leading to a ‘dropped door’ that sags in the frame are down to installation errors.
“If you look at the hinge and see that it’s failed, that’s often because the joiner has fit the wrong hinges,” he says. “In other cases, they might not have put the right fixings in, so the screws have come loose. Swelling in the door is another potential cause, especially if the room has been freshly plastered after installation.”
The solutions for a sagging door range from quick fixes with a screwdriver to challenging carpentry tasks. This article explains how to fix some of the most common causes of a door sagging – and when you might need to call in a professional.
The Door Company UK is an independent internal door fitting company based in Greater Manchester, specialising in premium doors and hardware across a wide range of styles including oak, glazed, fire doors, and pre-finished white. With over 30 years of industry experience, the company’s team of skilled joiners handle everything from the initial survey through to installation and final clean-up.
Experienced joiner Guy Davies founded his business in 2004. GLD Joinery provides a variety of services to homes and businesses in Leeds, Bradford and other areas of West Yorkshire, including kitchen fitting, door fitting and flooring installation.
Diagnosis: how to identify why your internal door is sagging
First, visually check the door and identify exactly where it is rubbing against the door frame. Is the point of friction on the jamb (the side of the frame where hinges are mounted), at the opposite side, or at the top or bottom of the frame?
“Open and close the door slowly and see where it’s catching or dragging,” says Bowes. “If it’s scraping along the bottom or catching at the latch side, that’s usually a sign that the door has dropped at the hinge side.”
Next, inspect the hinges and check for loose screws, gaps between the hinge and the door or door frame, or other signs that the hinge is not securely attached. The top hinge of a door takes more weight than the lower hinge(s), so this is a likely problem area. “Give the hinges a visual inspection and then try to wiggle the door gently; any movement when it shouldn’t move suggests loose screws or worn hinge leaves,” says Bowes.
In some cases, the door might not be perfectly sized for the frame. This can occur for various reasons, including imperfect installation of the door frame or movement in the surrounding structure (especially in period properties). “It’s worth checking the frame with a spirit level to see whether the issue is the door itself or the structure around it,” Bowes advises. “Shining a torch around the edge of the door in a darkened room can help you spot uneven gaps, which tells you a lot about where the misalignment is coming from.”
Step-by-step fixes for a sagging internal door
Method 1: tighten or replace the screws
The simplest solution for a sagging door is to adjust the screws where the hinge attaches to the door frame.
“This is always the first port of call because it’s the quickest fix and it solves the problem more often than you’d expect,” says Bowes.
“Remove one hinge screw at a time, and if it spins freely rather than biting, the hole has stripped. A short-term fix is to pack the hole with matchsticks and wood glue, let it dry, then refit the screw; it sounds a bit old school but it genuinely works.”
If the drive of a screw has become stripped, so you cannot gain purchase on it to turn the screw, then you might need to drill out the screw using a metal drill bit (meaning a drill bit that’s designed for drilling into metal).
“For a more robust repair, rather than going straight for longer screws (which come with larger heads that can create their own alignment issues), a better option is to reposition the hinge slightly on the frame, provided the frame itself is in good condition – even moving it by 10-15mm gives you fresh timber to bite into and a much cleaner result,” says Bowes.
“Fill the old screw holes with wood filler, let it dry, and you’re good to go. If the hinge leaf itself is worn or bent, just replace it; they’re cheap and it’s not worth trying to work around a hinge that’s past its best.”
Method 2: shim the hinges to improve alignment
Surprisingly often, the best solution to a household problem is to pack an ill-fitting component with a thin sliver of material called a shim. You can make your own shims by cutting off thin pieces of timber, or you can buy ready-made shims from a hardware retailer.
“Shimming is useful when the hinge recesses have been cut too deep, causing the door to sit proud on the hinge side and bind on the latch side,” says Bowes. “The fix is straightforward: remove the hinge, cut a thin piece of card or hardboard to the same size as the hinge leaf, and place it in the recess before refitting.
“You may need to experiment with the thickness to get the alignment right, so it’s worth starting thin and building up. It’s a small adjustment, but getting it right makes a noticeable difference to how the door hangs and closes.”
Davies suggests an alternative solution: refitting the hinge. “If there’s an even gap around the casing and there’s enough room in the frame, you can knock the hinge further in or replace it. Or, you can chop a bit of timber out of the casing to make room to refit the hinge – I do this with a hammer and a 25mm Marples chisel,” he says.
Method 3: adjust the strike plate
The strike plate is the metal panel on a door jamb that accepts the latch or bolt from the door itself. In some cases, this component causes problems with a door’s fit.
“If the door is catching on the latch or not closing properly but the door itself seems reasonably well aligned, the strike plate is often the issue rather than the hinges,” says Bowes.
“First, check whether the latch bolt is lining up with the hole in the plate; putting lipstick or chalk on the latch face is an old trick for marking exactly where it’s hitting.
“If it’s slightly out, you can often just file the strike plate opening to give a bit more room. If it’s more significantly misaligned, remove the plate, chisel out the recess a little in the right direction, and refit it in the corrected position. Fill the old screw holes if they no longer line up, and you’re good to go.”
Method 4: plane or sand the door
If you’ve considered all of the above options and you’ve concluded that the reason for your door’s fit issue is the dimensions of the door itself, then you might choose to plane or sand the door.
“Planing or sanding should really be a last resort once you’ve ruled out hinge and hardware issues, because you’re removing material you can’t put back,” says Bowes.
“If you do need to go down this route, take the door off its hinges and mark clearly where it’s binding – chalk or a pencil rubbed along the frame works well. Use a hand plane or belt sander and work gradually, checking frequently to avoid taking off too much material. If you’re planing the bottom of the door, a belt sander on the floor can be easier than using a plane.
“Bear in mind that if the sagging is caused by seasonal movement, the door might free up on its own in drier conditions, so it’s worth waiting a season before you start removing material permanently,” he adds.
Useful tools for fixing issues with internal door fit:
Marples chisels provide the sharp-edged precision needed for joinery tasks.
You can make your own shims to pack a door hinge, but some DIYers prefer to use ready-made shims cut accurately to various depths.
In extreme cases, you might need to plane material away from the edge of a door to get it to fit correctly. We'd recommend using a hand plane rather than an electric model for this delicate task.
FAQs
When should I call a professional to fix a sagging internal door?
Many joiners, carpenters and door specialists provide door maintenance services, and in some cases it’s best to get this household problem fixed by one of these experts.
However, Davies of GLD Joinery recommends giving this DIY project a go, before you call in the pros.
“Always have a go yourself before calling someone in, because you can save some money if you can manage it DIY,” he says. “If you can’t sort the hinge out or there’s another problem that you can’t figure out, that’s when to get help.”
Can a sagging internal door get worse or lead to other problems?
“A sagging door definitely has knock-on effects,” says Davies. “It can start taking paint off where the door is rubbing, and it might start loosening the handle, causing the fixings that hold the handle together to fail.”
When a door sags, this tends to place additional strain (through gravity) on the successfully installed fixings that are bearing its weight, so these may also be affected.
Are there cases where a sagging internal door needs to be replaced rather than fixed?
In some cases, sagging is a sign that a door requires replacement, rather than repairs.
“If the door frame itself is rotten, badly warped, or structurally compromised, no amount of adjusting the door will fix the root cause, and in these cases, you may need to look at replacing the frame,” says Bowes.
“Similarly, if there’s significant building movement or damp driving the issue, you need that addressed. Also, very old or damaged doors that have been planed repeatedly over the years can reach a point where there simply isn’t enough material left to work with, and replacement is the practical call.
“If you’re dealing with fire doors, it’s especially important to get a professional involved; they need to meet specific performance standards, and a poorly hanging fire door could be a safety and compliance issue.”
If you can fix a sagging door, then you're more than capable of solving all sorts of DIY problems for yourself. For more guidance on common fixes, read our guides on how to replace a door lock, fitting a toilet seat and how to change a light switch cover.
