How do you fix a double glazed window that won’t close?


Your home is your castle – the place where you and your family feel safe and secure. But when your home is riddled with draughts, it becomes less secure and more uncomfortable.

Not only do draughts cause you to feel cold and uncomfortable, they also allow valuable heat to escape, costing you money on your bills. But even more than that, they weaken the security of your home, leaving your family at greater risk of being burgled.

Main Causes of a uPVC Window that Won’t Close Properly

There are usually a few major causes of a uPVC window that is unable to close properly, these include the following:

  • Damaged hinges

Worn or damaged hinges are usually very obvious as you will be able to see a gap between the sash and the hinge side of the window frame.

  • Broken locks

If your windows are closed but you can easily slot a bank card into the sash and the frame, the lock needs adjusting to tighten the seal.

  • A broken sash window

Try shutting your window fully or as much as it will, look at the top corner above the handle and if you can see light leaking through the gap when you move the handle, your window has dropped and your sash may need to be replaced.

How to Fix a uPVC Window that Won’t Close

If your windows are broken, it doesn’t always mean they need completely replacing, in fact it may be just as cost affective to do minor repairs at a fraction of the price, this includes the following:

  • Replacing and fitting new hinges.
  • Adjust the window locks.
  • Repositioning glazing firmly into place.

Since uPVC windows are the UK’s most popular/common type of window frame material, we have focused the next few frequently asked questions solely on uPVC windows and their frames.

How do I free a stuck uPVC window?

If your uPVC window is stuck and won’t open, it’s always advised to seek the help and assistance of a professional window fitter, since attempting to open it yourself may result in further damage and repairs.

There are a variety of reasons that could be resulting in your uPVC windows being jammed shut, some of the most common include:

  • Worn rubber gaskets that have slightly melted and stuck to the frame.
  • Dirt, rust and oil may have deposited within the frame.
  • Worn handle spindles.
  • Double glazing lock repairs.

Check out our complete guide on the price of new windows, if you want a rough idea of how much you can expect to pay (including installation). You can also read about the various window styles available, as well as double glazing, triple glazing and decorative windows.

What’s the best way to prevent uPVC window faults?

Keep them clean: If you live in a climate with a lot of moisture, you’ll want to clean your uPVC windows on a regular basis. In fact, you should clean them every time the sun comes out to prevent mildew and build-up.

Use a window cleaner designed for vinyl, and be sure to rinse your windows well to remove all traces of cleaner. Pay particular attention to the area around the frame, the window itself, and the seals where the window meets the frame.

Essential uPVC care tips: 

  • Clean your uPVC frames with warm soapy water & a soft cloth every 6 months.
  • Clean the glazing at least every 6 months in low traffic areas and every 3-4 months in busy locations.
  • Lubricate working parts, like the hinges at least every six months, e.g. handles, hinges, locking systems.

Your uPVC windows and doors will inevitably get dirty over time, which is why it’s important to clean them regularly. You should be especially careful when it comes to the cleaning products that you use – harsh chemicals like bleach can cause a lot of damage to your uPVC frames and parts, which is why a warm water and a mild liquid detergent is much better.

You don’t need to use a lot of product either – just a little squirt will be enough to give your windows a good clean.

How do you know when it’s time to replace your uPVC windows?

Cracked, discoloured and faded uPVC windows are a clear sign that the material has reached the end of its lifespan. Similarly, warped, cracked and warped uPVC windows are also a clear sign that they’re beyond repair. If a window is badly cracked, it’s a good idea to replace it rather than attempt to repair it.

Here are the major signs that it’s time to replace your windows rather than simply repair them:

  • Increased noise levels from outdoors.
  • Increased energy and heating bills.
  • Condensation in between the windowpanes, impacting the ability to see through them.
  • Very draughty window frames.
  • Persistent double glazing lock repairs.
  • Damaged, discoloured or warped frames.
  • Single glazing that’s poor at keeping draughts out of your home.

Why is there condensation on my double glazed windows?

Luckily, most condensation is harmless. On the outside of your windows, condensation isn’t a problem as long as it’s not on the glass itself. If it is on the glass itself, it means that the pane is Warmer than the room, which is bad for your heating bills.

However, on the inside of your windows it means that the pane is doing its job properly; losing heat, which makes the inside pane of glass the cool, and preventing the build-up of moisture within the home, which prevents the formation of mould and mildew within the home.

Ultimately, if the condensation is on the inside of the glass, it’s a sign that your window is leaking and needs replacing.

Get a Free Quote for your New Double Glazed Windows Today

The number one advice when shopping for new windows for your home is to secure at least three quotes from local installers.

Your priority shouldn’t necessarily always be price, since the reputation of the company, aftercare and the warranty are also all important factors.

Going for the cheapest may mean paying less upfront, but in the long term you may pay more in terms of time, stress and repairs.

Here at Window Central, we have a network of reliable and trustworthy window installers throughout the UK. Request your free quote now and you should receive a range of quotes from our network in the next 24 hours (at the latest).

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