How to Open a Jammed, Stuck, or Seized uPVC Window

I couldn’t open the window, it was stuck, jammed and seized shut. The window handle moved, but the window just won’t open?

Description:

When you close the window, the gearbox (which is attached to the handle) pushes shootbolts (espag or espagnolette) and roller cams (mushrooms) out to lock the window in the outermost corners. Parts of the gearbox can break, or the shootbolts can seize preventing the window from opening.

Topics:


uPVC Window Lock Faults:

The window handle gearbox can break (which is often the case), or the shoot bolt (espag or espagnolette) and roller cams (mushrooms) jam or seize. When the gearbox breaks, it doesn’t allow the shoot bolts and the roller cams to return to the open position, and the window won’t open.

Typical Window Gearbox Faults:
uPVC Window - Broken Locking Mechanism (Gearbox Lug)
uPVC Window – Broken Locking Mechanism (Gearbox Lug)

This image shows a lug that has broken off. The gearboxes use cast components which can be brittle.

uPVC Window - Broken Locking Mechanism (Gearbox Actuator)
uPVC Window – Broken Locking Mechanism (Gearbox Actuator)

And this image shows the operating arm broken away from the window gearbox.

uPVC Window Lock – Parts Description:

Note: The parts below are for illustration only, as they come in different shapes and sizes from various manufacturers… uPVC and PVCu are the same material, just a different pronunciation.


How do I Open the Jammed or Seized Window?

It’s a fairly easy process to open the window. The difficulty is when there is:

  • Only a small gap to insert a simple tool,
  • Or, the roller cam is stiff to move (corroded or seized).
  • Parts are missing (roller cams).

Precautions

It may seem daft, but… Please don’t fall out of an open window, it’s easily done. Be careful, be safe!

  • uPVC windows are made of soft plastic and can easily be damaged, scratched or gouged.
  • When working on a window, beware of dropping tools and other things out of the window. “Lucky” the cat might not be so lucky..?

Any modifications are at your own risk…

Easy to Open Example (Difficult to Open Example below):
The handle moves but the window just won’t open? – Easy to Open Example

The text and images below, describe how we open a jammed or stuck window…

Tools:

You will need something fairly thin bent at a right angle. You could use a:

  • Bent nail.
  • Allen key.
  • Or a pick.
  • And pliers to help pull the tools.
uPVC Window - Jammed, seized or Stuck Window - Tools
uPVC Window – Jammed, seized or Stuck Window – The Tools Required

Once you have your tools, it’s trial an error to see which one fits best? Each window may have a different size gap between the window and frame, (and the gap can be different from one end of the window to the other…).


Inserting the Opening Tool in the Window Gap:

Where do I Insert the Tool?

The shootbolts are towards the opening ends of the window, above and below the window handle (side-hinged window), or to the left or right of the handle (top-hinged window) – See the image below.

uPVC Window - Jammed or Stuck Window - Shootbolt Positions (Top and Side Hung)
Jammed or Stuck uPVC Window – Shootbolt Positions (Top and Side Hung) Windows

Opening the Jammed uPVC Window – Moving the Shoot bolt Roller Cam:

  1. Put the window handle in the open position. This will move any working shootbolts to the open position.
  2. Insert a right-angled tool just past where the shoot bolt roller cam is likely to be (so the roller can be pulled towards the window handle – See the images below).
  3. Push the tool between the window and the window frame, past the rubber seal. Be careful not to damage the seal or the plastic window.
  4. Turn the tool through 90 degrees. Gently pull the tool towards the shoot bolt roller (in the direction of the window handle). Position the tool so it runs along the edge of the window. This is to ensure you don’t miss hooking the roller cam.
  5. You should then feel the tool stop as it hooks the shoot bolt roller.
  6. Pull the shoot bolt roller cam towards the window handle.
  7. The shootbolt roller should move and release this end of the window.
  8. Repeat if the opposite end of the window is also jammed?
  9. The window should now open.

Notes:

  • If needed, have a look at another window (on the ground floor) that has the same mechanism, to familiarise yourself with how the lock works and where all the parts are fitted.
  • Make sure you are pulling in the right direction (in the direction that the shootbolts move to open).
  • Both shootbolts can get stuck, so you may need to release both sides.
  • Don’t forget to make sure the handle is in the open position, when trying to open the window that is jammed.
  • Use some cardboard or something similar between the window and your tools to try and protect the window from scratches.
  • If needed, use a screwdriver to increase the gap to get the tool in.
  • You may need to use a pair of pliers to grip the allen key (or right angle tool).
  • You may need to remove the window handle if it gives you more room.

It can sometimes be a very easy job. It’s difficult when you can’t get the tool in the small gap, or the shootbolt mechanism is stiff or seized.

Opening a Stuck PVC Window – Demonstration (with an open window)

Video Examples:

Difficult to Open Example:
The handle moves but the window just won’t open? – Difficult to Open Example

Repairing a Jammed or Stuck uPVC Window:

The repair will usually involve either:

Freeing up or Replacing the Shootbolts and Roller Cams.

The shoot bolts and their rollers can become seized or corroded, as they are usually manufactured from mild steel with a thin electroplated finish.

Free up, clean and protect from further corrosion. Lubricate, or replace as necessary. Silicone grease is a good lubricant for windows. It less likely to get washed away, won’t damage any rubber seals and is usually a transparent white colour (often used in plumbing applications).

Replacing the Window Locking Mechanism Gearbox:

Lugs can break off within the gearbox, or the casting can just fracture. To replace, remove the window handle and loosen the shoot bolts. You can then slide the gearbox out of the window frame (see the images below).

When you replace the gearbox, you can insert the gearbox in the window frame the wrong way round. All this does is change the direction that the window handle operates. Try the handle in the gearbox before you fit it in the window, or just turn the gearbox through 180 degrees.

Note:

As a temporary solution, you can often refit the shoot bolt gearbox without the shoot bolts (espag or espagnolette), so your window will still close and lock (by the handle latch only) whilst you wait for parts.

Checking the Connection Between the Locking Mechanism Gearbox and the Shoot bolts:

In some instances, the shootbolt can become disconnected from the handle gearbox. Refit, checking that the connection lines up correctly and is secure.

Note:

When uPVC windows are manufactured, the shoot bolts are sometimes cut to length to fit the window. In some cases, they can be cut too short and can jump out of the housing. If this is the case, the shoot bolt (espag or espagnolette) may need replacing.


Opening a Jammed uPVC Window – Hints and Tips:

If it helps, practice on an open ground floor window (that has the same fittings), to see how the mechanism works and where all the parts are. It may give you an idea on what’s needed to open the stuck window. You will probably need to operate the window handle at the same time when testing. With the windows that are stuck shut, make sure the handle is in the open position (when trying to open).

As usual, any work is at your own risk… Please be careful, as it’s very easy to fall out of an open window. Be safe!

  1. Place thin cardboard against the window to help protect the plastic…
  2. When trying to open a stuck window, make sure the handle is in the open position…
  3. Which way round do the window handles go?
  4. My upvc window lock does not have the mushrooms but the locking mechanism is the same style. Any idea what I could do?
  5. I have windows with the shoot bolts but not the rollers and one of the shoot bolts is not unlocking?
  6. When I get the window open, will I be able to close it?
  7. My window is open and it won’t close?
  8. I am unable to twist the allen key, probably not enough space between window and the frame… any suggestions?

1. Place thin cardboard against the window to help protect the plastic…

Thin cardboard can protect the soft window frame plastic from getting damaged. You could hold the cardboard in place with masking tape.

2. When trying to open a stuck window, make sure the handle is in the open position…

Don’t forget to make sure the handle is in the open position, when trying to open the window that is jammed.

3. Which way round do the window handles go?

For verticle window’s it’s easy, as the handle normally point downwards. For top hung windows (horizontal), imagine for a moment that you have turned the window sideways, and the window is now side hung (vertical). This gives you a good idea which way round the handle should go.

4. My upvc window lock does not have the mushrooms but the locking mechanism is the same style. Any idea what I could do?

Have a look at another window (with the same mechanism) to work out if there is a method of opening – Choose a window on the ground floor, as you don’t want to fall out the window!

There may be some holes somewhere in the mechanism (shoot bolts) that you could grab with a pick. Practice, investigate with another open window (on the ground floor) to see if you can to work out a method of opening?

Removing the handle or jiggling it around whilst using a pick may help?

5. I have windows with the shoot bolts but not the rollers and one of the shoot bolts is not unlocking. I had a look at one of the other windows at my house and can’t think of a way of pushing them in with the window stuck shut. Any ideas?

Looking at another window (on the ground floor, so you don’t fall out!), are there any holes where rollers could have been fitted? You could try and make a ‘u’ shaped tool to grab the shoot bolt. If there is absolutely nowhere to grab the shoot bolt and there is no way of hooking it, then the only option may be to grab it from the other side?

As always, this is at your own risk… If you remove the glass (remove the plastic beads around the glass edge – Older windows outside edge, newer windows inside edge). The frame will flex slightly more. Be careful though as things can break (the plastic welds holding the window together can be brittle and the hinges can break). You might be very lucky if the window flexes a bit, and the shoot bolt is only just latching?

Warning – I have never done this, (and it is the last resort). The whole window is usually held in place by drilling through the plastic frame and fixing using long screws. On the same basis, if the shoot bolt needs a small hole drilled in it, you could drill through the frame from where the glass was fitted. Choose the best position to drill through carefully by comparing the shoot bolt position on another window (on the ground floor).

If the shoot bolt still cannot be moved using a pick, make the start of the hole (in the plastic) bigger. The aim is to make a funnel type hole so that the shoot bolt can be levered up using the hole drilled in it. Failing that, make an inspection hole through the plastic frame to get to the shoot bolt from the other side. You may need to jiggle the handle to get the shoot bolt to move. The hole(s) you drill will need to be hidden when the glass and shootbolt are replaced.

6. When I get the window open, will I be able to close it?

If it’s the gearbox that’s broken and it’s not operating the shootbolts properly (moving them in both directions), you can remove the shootbolts (top and bottom, or left and right) and just leave the window lock (next to the handle) in place. The window should still open and close. Check that the window lock operates freely when you have removed the shootbolts.

Note: Your house insurance may stipulate the type of locking mechanism that should be fitted to a window. So you may need to replace the broken parts.

7. My window is open and it won’t close?

The gearbox fitted inside the window (the handle shaft passes through it) has probably broken. To shut the window, you will need to remove the shootbolt(s), as one, or both have probably not retracted.

The shootbolts are normally held in place by screws, but are sometimes pop riveted. If you manage to move the shootbolts (without removing) and shut the window, it probably won’t open again by the handle (because of the broken gearbox). You will then have to use an allen key (or something similar) to open the window.

8. I am unable to twist the allen key, probably not enough space between window and the frame… any suggestions?

Sometimes you have to use a screwdriver to increase the gap to get the tool in, and use a pair of pliers to grip the allen key. Use some cardboard or something similar between the window and your tools to try and protect the window from scratches.

  • Have a look at another window (on the ground floor) that has the same mechanism, to familiarise yourself with how the lock works and where all the parts are fitted.
  • You may need to remove the window handle if it gives you more room.
  • Make sure you are pulling in the right direction (in the direction that the shootbolts move to open).
  • Both shootbolts can get stuck, so you may need to release both sides.

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