7 Most Common uPVC Sash Window Problems and How to Fix Them
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What Can Go Wrong With Sash Windows?
Poor window installation can cause serious problems, especially with sash windows. Installation errors, such as misalignment or improperly fitted components, can cause operational issues, such as the sashes not sliding correctly or becoming stuck. If the frame is not level or the sashes aren’t properly balanced, it can put unnecessary strain on the moving parts, leading to long-term damage, costly repairs, or even replacement windows.
In addition to installation issues, aged and poorly fitted sash windows can also present significant maintenance concerns. Over time, components may deteriorate, causing draughts, condensation between the panes, and a reduction in energy efficiency. Regular maintenance is essential for uPVC sash windows to continue to function smoothly, but when the window has been poorly installed or becomes too worn, it may be time to consider a full replacement to avoid further problems.
- Sticking or Jamming Windows
- Draughts and Poor Insulation
- Condensation Between Glass Panes
- Water Leakage
- Faulty Locks and Handles
- Rattling or Noisy Windows
- General Wear and Tear
Difficulty Opening And Closing Due To Sticking Or Jamming
A question our service engineers are often asked is ‘Why won’t my uPVC sash window close?’ There are a few reasons why you may have issues with your windows closing properly, but often the cause is down to the installation process. If you have packed or foamed your sash windows too tight while installing, this is likely to make them stiff and you may have issues opening or closing the sashes.
If you’ve installed fixing straps on the windows, a screw may have been positioned in the path of the shoe, preventing the sash from sliding upwards. Similarly, if you’ve fitted shutters, blind hooks, or any other fixtures to the outer frame of the window after installation, a screw could have been placed in the shoe’s path, once again causing operational issues.
How do you fix a stuck sash window?
If the sashes tilt without issue, the bottom sashes can be adjusted using the shoe bar beneath the sash. If your windows have been manufactured with constant force, the coils may be running dry, which can occur due to building dust, plaster dust, or similar debris. This can be resolved by applying a silicone spray to the coils. Avoid using WD-40.
Why Is My Sash Window Not Staying Up?
Your balance may have become disconnected, which can occur if the window has been carried or stored on its side. Our windows should always be handled in an upright position, as failing to do so can affect the balance tension.
Poor Insulation Leading To Draughts
If your windows weren’t installed correctly, this could result in draughts in your home, which can lead to heat loss and even higher heating bills. To address potential draughts in your sash windows, there are a few checks you can easily complete. The bottom sash should sit evenly across the sill when the window is closed. The top sash should fit evenly across the head when the window is closed. Additionally, the gap along the woolpile on the sides should be consistent at the top, middle, and bottom.
How can I draught proof my sash windows?
Draught-proofing your sash windows involves sealing any gaps that allow air to pass through while maintaining the window’s smooth operation. Please note, because of the closing system of a sash window, it will never be 100% airtight. Start by inspecting the frame and sashes for gaps around the edges, particularly where the sashes meet the frame and where they slide past each other. Applying weatherstripping or brush strips along these areas can create a brush seal without interfering with movement. You can also fit a draught excluder along the meeting rail and around the bottom of the sash.
Regular maintenance, such as keeping the channels clean and the sashes correctly aligned, can further help to minimise draughts.
Condensation Between The Glass Panes
Why does condensation occur between glass panes?
Condensation between the glass panes of sliding sash windows typically occurs when the seal around the double glazing has failed. This failure allows moisture to enter the space between the panes, which can lead to persistent condensation. Over time, this trapped moisture creates the perfect conditions for mould growth, which can affect both the appearance and hygiene of your windows.
Seal failure can result from factors such as misalignment caused by temperature fluctuations, which place stress on the window frame and seals. To resolve this issue, the affected glass unit will usually need to be replaced.
If you’ve seen water within your sash window glass panes, you’re likely wondering how to fix moisture between window panes. Unfortunately, once condensation has gotten between the glass, a completely new glass unit will be required.
Water Leakage
Our sliding sash windows are designed to achieve exceptional watertight performance, helping them stand up to even the harshest weather conditions. During rigorous testing, our windows were subjected to an intense spray of eight litres of water per minute for a full 40 minutes. Our windows demonstrated zero leakage, highlighting their robust engineering and superior design.
This outstanding performance earned our sash windows the Class 6A classification for watertightness, a testament to their quality and reliability. Whether facing heavy rain or strong winds, our windows can keep your home dry and comfortable, providing peace of mind and long-lasting protection.
If you’re experiencing water leakage, the first step is to ensure that the windows are fully closed and securely locked, as an improper seal can often be the culprit. If the issue persists, carefully inspect the windows for any visible gaps or damage that could be allowing water to penetrate. Pay close attention to the seals, frames, and surrounding areas. It’s also important to thoroughly investigate where the water is coming from, as leaks can sometimes originate from unexpected places, such as nearby building features or drainage systems. Identifying the exact source is crucial to resolving the problem effectively.
Faulty Locks And Handles
I’m not able to lock my sash window, what do I do?
Start by making sure the top sash has an even gap all the way along the top, and the bottom sash has an even gap along the bottom. If there are larger gaps at the ends of either sash, it could indicate that the head or sill is bowed, preventing the sashes from reaching their proper positions and causing the window to fail to lock. If there is a gap at opposite corners, such as the bottom right on one side and the top left on the other, it suggests the frame has been fitted out of square, which will also stop the window from locking.
Replacing a damaged or faulty lock on one of our sash windows is straightforward. Simply unscrew the screws on the cam and locking keep, then fit the new lock in place.
Rattling Or Noisy Sash Windows
Rattling or noisy sash windows are often a sign of wear and tear or improper installation. Over time, gaps can develop between the sash and the frame, allowing the window to move when exposed to strong winds. This movement not only causes the rattling sound but can also reduce the window’s energy efficiency by allowing cold draughts to enter. Ensuring the sashes fit snugly within the frame and checking for worn or damaged components, such as loose brush seals or misaligned parts, can help address the issue.
In some cases, rattling can occur due to the age of the window or environmental factors, such as changes in temperature causing materials to expand and contract. Regular maintenance, such as lubricating the moving parts and inspecting the hardware, can also prevent the problem from worsening and keep your sash windows smooth and quiet.
uPVC Sash Windows Average Life Expectancy
How long should sash windows last?
With proper care, uPVC sash windows can last for decades. The exact lifespan, however, depends on various factors. Windows installed in exposed environments, such as open areas or even near the coast, may require replacement sooner than those protected from direct sunlight and extreme weather. In general, well-installed and well-maintained sash windows that are not exposed to severe conditions typically have a lifespan of plus/minus 25 years.
While uPVC requires much less maintenance than traditional timber windows, regular cleaning can help improve your windows’ life expectancy. We recommend cleaning all products with hot, soapy water and avoiding harsh chemicals, particularly on woodgrain or painted finishes. For our uPVC sliding sash windows, a silicone spray can be used to lubricate the moving parts, such as the springs. Avoid using WD-40!
You can find a detailed overview of maintenance suggestions for uPVC sliding sash windows on our dedicated webpage.
Can uPVC Sash Windows Be Repaired?
Yes, uPVC sash windows can often be repaired, depending on the nature of the issue. Minor problems, such as draughts, rattling, or difficulty in operating the sashes, can typically be resolved by adjusting or replacing components like weatherstripping, balances, or locks. Broken or damaged hardware, such as handles or cam locks, can also be replaced with ease, restoring the functionality of the window without the need for a full replacement. If the windows are sticking or not sliding smoothly, cleaning the frame jambs and applying a silicone spray can help resolve the issue.
However, for more significant problems, such as if the uPVC frame itself is cracked, warped, or extensively damaged, replacement may be a more cost-effective and long-lasting solution. Regular maintenance can significantly extend the lifespan of uPVC sash windows, keeping them in excellent condition for years to come.
When Should I Replace My Window Sash?
You should consider replacing your window sash if you notice significant damage or deterioration that affects its performance. If you start to see warping or distortion of the frame, especially if this causes operational issues such as difficulty sliding or tilting the sashes or maintaining a proper seal, this can be a key indicator that replacement is necessary. Other signs include persistent draughts, condensation between double-glazed panes, or excessive noise from rattling that cannot be resolved with repairs. In some cases, replacing the sashes can keep your windows energy-efficient, secure, and easy to operate, providing long-term benefits for your home.
If you have any further sash window maintenance questions, visit our Frequently Asked Questions page, or get in touch with our customer care team via our contact form.
If the time has come for replacement sash windows, get a price on our website.
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- Ultimate Guide to Sliding Sash Windows
- Will Quickslide Sliding Sash Windows Withstand Draughts and Leaks?
Their knowledge and expertise have been honed by working closely with the rest of Quickslide’s extensive team of professional manufacturers, letting them learn the ins and outs from direct sources. Their B2B experience is further enhanced by Quickslide’s long list of trade partners, offering additional insight into the manufacturing and installation process of sash windows, bifolds, flush windows, patio doors, and more.
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Please note, our news articles are relevant and accurate at the time of release, but as technical developments dictate, and times goes by the information in this article may no longer be applicable. If you have questions, please contact us using our online contact form or call us on 03332 412 240.
