uPVC Problems and Prevention’s

uPVC, or Unplasticized Polyvinyl Chloride, is a building material that is frequently used to make doors and windows for homes. It is becoming more popular than using wood as it is often a cheaper, more energy efficient and a more durable alternative. The upkeep of uPVC doors is also a lot less hassle than caring for wooden doors as it only needs a wipe down with a damp cloth every now and then.

But it doesn’t come without its problems; our Locksmiths often face the same common issues homeowners experience with their uPVC doors. To see what the most common occurring issues uPVC doors cause and tips on how to prevent those issues take a look at our blog below!

locksmith with upvc window



Arguably the most common problem homeowners face with their uPVC doors is during very hot and very cold weather. Like wooden doors, uPVC doors expand and contract slightly in extreme weather and can cause the door or window to become stiff and ‘sticky’.

uPVC doors can expand up to 2.4cm in temperatures reaching 40°C which can cause people to become locked out or locked in, in their own homes. We consider these cases an emergency at Keytek® and aim to get a Locksmith out to help within the hour!


Unfortunately, there is no fool-proof way homeowners can prevent their uPVC doors expanding and contracting as we cannot control the weather. However, it is worth spraying your door with cold water or patting it down with a cool damp cloth to try and reduce the heat retention. During the cooler months do not reverse this advice and put hot water on your uPVC doors as this may cause it to crack.




Continuing on from our expanding problem, extreme temperatures as we know can lead to doors shrinking and expanding and once the door has settled back to its normal size the door may become unaligned. Signs of a misaligned uPVC door include the door sagging or catching at the door frame. Notice if the corners of the door and the frame are aligned, whether the door is level and if the gaps between the frame and the door are a consistent difference throughout.


Constant use, rough handling and slamming doors over time may lead to uPVC doors becoming misaligned so it is quite likely that homeowners will experience a misaligned door in their lifetime. Again, there isn’t a awful lot homeowners can do to prevent their doors becoming misaligned apart from taking good care of the door and even doing so doesn’t 100% guarantee that the door won’t ever suffer from this problem.

In misalignment cases it is best for a trained Locksmith to be called out to fix the problem as this is their bread and butter and will ensure the problem is fixed without causing further issues which end up becoming more costly.

screwing upvc door

Pressure on lock


A jammed lock; putting too much pressure on the centre case of the lock can cause sections on the inner compartments to break and effectively will jam the lock and causes homeowners to get locked out or in their homes.


Less pressure applied to the lock will certainly aid the longevity of it. Avoid allowing the bolts to grind when lifting up the handle as this will put less pressure on the centre case. Lubricating the bolts with WD40 is another great way to keep the lock in the best working order as not only will it keep the mechanisms running smoothly it’ll will clean them too!


Lock Snapping


uPVC doors are often subject to lock snapping, which is a common technique used by burglars to easily gain entry into their victims homes. Lock snapping requires no specialist tools or knowledge and thieves are able to snap the lock and gain entry in as little as 5 seconds.



The best way to prevent this problem is to insert anti-snap locks. On a standard cylinder a thief is able to apply force and snap the lock which exposes the mechanism and makes gaining access easy. Whereas an anti-snap cylinder has an indentation (sacrificial snap line) cut into the body which acts as a buffer so that if force were applied, the body would snap at this purpose built ‘weak point’ and won’t expose the mechanism, leaving it intact.

The most secure anti-snap locks are the ones inscribed with a TS007 3 Star standard Kitemark as these locks are protected against every single break-in attempt.


Cylinder Fitted Incorrectly


A poorly fitted cylinder leaves homeowners subject to burglary. If the wrong cylinder has been fitted to the door or if the cylinder is left protruding more than 3mm from the handle than the home is vulnerable to opportunistic thieves who notice the door would be easily accessible.



A fully trained Locksmith such as ours here at Keytek® will always ensure that the correct lock is used and properly fitted within the door. Our Locksmiths will also offer the best security advice to homeowners so that they can secure their homes as best they can such as explaining the different levels of security locks.


Cold Windows


Another worry we’ve heard is that the inside of double-glazed windows feel cold to the touch. This is actually a good sign as it means the windows are working correctly. Glass is an insulator and double-glazing has been innovatively designed to trap in the cold air and keep the room warm. Double-glazed windows are also filled with an odourless, colourless and non-toxic gas between the panes which entraps even more heat.


If the windows are double-glazed and in working order then there will be no problem to prevent. It is recommended that you upgrade your windows every 20 years to keep them in tip top shape but if looked after well double-glazed uPVC window can far suffice that time frame. Another way to keep the heat in during the winter months is to keep the curtains closed as it acts as another barrier the heat has to go through to escape.



The best way to ensure problems with uPVC doors and windows are minimized is to hire a professional Locksmith. Our Locksmiths at Keytek® are all fully accredited and fully DBS checked. They aim to arrive within 30 minutes – 1 hour for emergency cases, e.g. if someone were locked out of their home and offer the best security advice to all our customers.


upvc window overlooking sea