Why Your uPVC Door Lock is Sticking and How to Fix It (Dorset Guide)

A stiff or sticky lock on your uPVC door is more than just an annoyance—it's a critical warning sign that your locking mechanism is under stress. Ignoring this issue can lead to a total mechanism failure, potentially leaving your property unsecured or, worse, locking you out entirely. As the most common type of modern door in Dorset, uPVC systems require specific care. Here is a guide to diagnosing and fixing the problem, including when you absolutely must call an expert.

Diagnosing the Problem: Is it the Lock or the Door?

Before you reach for the lubricant, you need to identify the root cause. This often falls into two main categories:

• Door Misalignment (Common): Over time, due to daily use or extreme temperatures, uPVC doors can expand, contract, or "drop" slightly within the frame. When this happens, the key will feel stiff because the moving parts of the lock are no longer perfectly aligned with the strike plate in the frame.

• Mechanism Failure: If the key is stiff even when the door is open (not engaging the frame), the issue is internal. This is usually due to debris, lack of maintenance, or a broken gearbox.

Quick DIY Fixes for a Sticking uPVC Lock

You can often resolve minor sticking issues yourself:

• Lubrication: Use a silicone-based lubricant spray or graphite powder blown lightly into the keyway and around the moving parts. Crucially, avoid oil-based products like WD-40, as they attract and trap dust, which can gunge up the delicate internal mechanism.

• Check and Tighten Screws: Loose screws on door handles, the lock cylinder, or the strike plates can cause the mechanism to malfunction. Carefully tighten all visible screws with a suitable screwdriver, ensuring you do not over-tighten, which could strip the threads.

• Clear Debris: Regularly clear dust, dirt, and debris from the door frame and the keyway.

When to Call Peters Locksmiths

If your key is stiff when the door is closed, or if the key turns but doesn't operate the mechanism, the problem is beyond a simple DIY fix. This indicates a potential gearbox failure or a major misalignment.

Local Authority Check: In the Dorset area, we often see Lock Corrosion and uPVC Gearbox Failuresdue to coastal salt air. Regular service prevents these coastal issues.

Final Call to Action: Don't wait for your door to fail completely. If your uPVC lock is still sticking after basic maintenance, call a local specialist. We aim for a rapid 30-minute emergency response in the Bournemouth, Poole, and Christchurch areas. Call Peter directly on: 07304 073538.