If you are starting to feel a slight draught while sitting near your window, or noticing a bit of persistent fog between the glass panes, you are likely asking the golden question: how long does double glazing last?
At Select Windows, we know that new windows are a significant investment. You want to ensure that when you hit “buy,” you’re getting decades of performance. In this guide, we’ll break down the typical lifespan of uPVC windows, what causes them to fail, and how you can make yours last as long as possible.
The Short Answer: How Long Should Double Glazing Last?
On average, high-quality double glazing should last between 20 and 35 years.
However, this isn’t a “set it and forget it” number. The actual double glazing lifespan depends heavily on three specific factors:
- The Quality of Manufacture: Not all uPVC is created equal.
- The Precision of Installation: Even the best window will fail in five years if it isn’t fitted square and sealed correctly.
- Location: Windows facing south or those on the coast (exposed to salt air and high winds) often have a slightly shorter life than those in sheltered areas.
Understanding the Lifespan of uPVC Windows
When people ask “how long do uPVC windows last?”, they are usually talking about the frames. Modern uPVC is incredibly durable – it won’t rot like old timber or rust like metal.
- The Frames: These can easily see you through 30+ years if wiped down occasionally.
- The Gas Fill: Most units are filled with Argon gas to provide insulation. Over time, this gas can slowly leak out (usually at a rate of about 1% per year).
- The Seals: This is usually the “weakest link.” Once the rubber seals perish, the vacuum is lost, and the window’s efficiency drops.
5 Signs Your Double Glazing Has Reached Its Limit
You might not need to replace every window at once. Here is how long double glazed windows last in practical terms – once you see these signs, the “lifespan” is effectively over:
- Condensation Inside the Panes: This is the big one. If there is moisture between the two sheets of glass, the seal has blown. The window is no longer providing thermal insulation.
- Draughts: If you can feel air moving even when the window is locked, the frame may have warped or the gaskets have flattened.
- Difficulty Closing: If you have to “heave” the window up to lock it, the hinges or the frame itself may be failing.
- Outside Noise: If the street suddenly sounds much louder than it used to, your soundproofing seals have likely degraded.
- Water Leaks: If water is pooling on your internal windowsill after a storm, it’s a clear sign that the drainage or weather seals are gone.
Can You Extend the Life of Your Windows?
While you can’t make a window last forever, you can certainly push it toward that 35-year mark with a little bit of TLC:
- Oil the Moving Parts: Once a year, use a light machine oil on the hinges and locking mechanisms.
- Clean the Gaskets: Avoid harsh chemicals. Use warm soapy water to keep the black rubber seals supple.
- Keep the Tracks Clear: Vacuum out the dust and grit that accumulates in the frame tracks – this prevents the “grinding” that ruins hinges.
Is It Time for an Upgrade?
Knowing how long do double glazing windows last helps you plan your home maintenance budget. If your windows were installed in the 1990s or early 2000s, you are likely nearing the end of their effective life.
Newer windows don’t just “not leak”- they are significantly more thermally efficient than those made twenty years ago, meaning they could actually save you a tidy sum on your heating bills.
Not sure if your windows have “blown” or just need a service? Contact Select Windows today. Our local experts can assess the current state of your glazing and give you an honest appraisal of whether you need a repair or a full replacement.