uPVC windows problems and pitfalls

With new architectural trends we are seeing more and more glass on new buildings and renovations – the big bi-fold doors, roof lights, even goldfish-bowl style windows that wrap around corners.
People want light, they want a feeling of space, and as technology develops, glass is becoming more energy efficient.

image of property with windows as main feature

However, windows can come with a whole host of problems, as we see in our every-day surveying work. And surprisingly, although it won’t warp or decay like wood, we see a lot of problems with uPVC double glazed windows.

Many homeowners think these windows will last forever and that you don’t need to ‘look after’ them. But that’s far from the case – especially if you live in coastal areas like Folkestone or Hythe where one of our offices is based. We’ll get to why later.

During our building survey inspections and homebuyer reports, we have seen a whole host of problems from defective mechanics (the locks and handles), to damaged seals and foggy panes. And not only that, as our lovely South East area gets more and more sunshine and heat, the uPVC frames, if not specially formulated to protect them from UV light, will begin to deteriorate. They’ll go brittle, or yellow, because of the UV light.

We can usually tell the age of windows by looking at the frames and gap between the glass panes – older windows may be 16mm or less, but modern windows are usually over 20mm. Helpfully, there is quite often a manufacturing date stamped on the frames – open the window and look on the jamb, or sometimes its printed between the panes.

So what types of problems do we find?

We hinted at it earlier, but one of the big problems we see locally is rusting and damaged screws, locks and hinges, where the salty air has corroded the metalwork. Many people leave their windows open, or on vent, so they don’t get moved regularly and become stuck or stiff to open or close. Most people realise this when they decide to close all their windows before going on holiday. Homeowners should give these a regular clean and products are available to loosen up your windows.

At the bottom of windows there are usually small oblong holes – these are drain holes to allow any water that gets in the frames to drain out. But we regular see these blocked, which means water in the frame cannot drain out and internal dampness develops – often beneath the window. We also see drainage holes blocked where people don’t keep them clean.

Weak handles and catches, especially in budget windows where savings are made with cheap cast fittings are another common problem.

Another common problem is condensation between the panes of double glazing. This is caused when seals have eroded around the edge and they allow water vapour in. Usually it happens to windows at least 15 years old, but it can an happen with relatively new windows so is something to keep an eye on.

Installing windows

Other problems with uPVC windows are nearly always related to poor installation – that’s the key thing. If you are having new windows installed, always use a reputable installer. Check out their reviews online and talk to people about who they have used and what their experiences are. Make sure you use a trader registered with FENSA and that there is a good warranty period with an insurance protected guarantee.

You don’t normally need planning consent to replace windows, unless you have a listed building, or the property is within a Conservation Area (where it usually applies just to the front facing part of your home). But, Building Regulations do apply to replacement windows installed after April 2002 (but not if you are simply replacing the glass).

When windows are installed it is very common to see the opening bigger than the actual frame, leaving slight gaps at the edges. A good installer will have measured properly in the first place, but sometimes it can’t be helped if they are slightly out as brickwork, especially on older buildings, may not have perfect lines. If the windows are not properly sealed it risks damp problems and leakages, especially at the bottom of frames. (You can often tell if you can see lots of spray foam poking out around the window.)

Energy efficient windows

Other issues with windows can affect those that have been purchased with efficiency in mind, such as low emissivity and gas-filled windows. They can be more expensive to install, but they usually help reduce energy bills in the long term.

Low emissivity glass is great at blocking the UV light that can come into your home, and also helps regulate the temperature by blocking heat and cool both in an out. However, you can get a slight haze on the window. If you see this, it doesn’t mean it’s damaged, it might be low emissivity glass.

Gas filled windows may need to re-filled over time. They have a slow natural leakage and this will affect their energy efficiency eventually. Their seals are generally very tight to ensure it isn’t lost via a poor seal, but these should always be checked.

The last word

When you move into your new home, you may want to ensure you have the windows warranty transferred into your name. If the windows are fairly new it is well worth it. There may be an admin fee, but it will be worth it against not having cover on your warranty. It won’t cover all the issues we have mentioned here, but it will certainly cover some – just make sure you read the warranty T&Cs through and that you are clear on what is covered.

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