Considered the most popular material for modern windows, is uPVC or unplasticised Poly-Vinyl-Chloride. It’s robust, low cost, and lasts for many years with minimal maintenance. To keep yours looking tip-top, you only need give it the occasional wipe with a damp cloth.
Over time, certain sorts of uPVC are prone to slight discolouration. Those brilliant white frames, if exposed to the elements for long enough, will turn an ugly shade of yellow. He we take a look at this problem, why it happens, and see whether there’s anything that can be done once your uPVC has turned yellow.
What Makes Upvc To Turn Yellow?
There are several things that can cause uPVC to turn yellow, but the most likely culprit is exposure to UV light. You may notice that your windows aren’t yellow in certain places where the sunlight is restricted, your south-facing windows, as an example, may be most affected.
One of the biggest advantages of uPVC is that it is recyclable, and as a result it is environmentally friendly. But it’s for this reason that not all uPVC windows are created the same. If your window has been manufactured using extra plasticizing agents and pigments, then it may be more prone to discolouration.
How Not To Whiten Your Yellowed Upvc Windows
Having located the problem, we’re left with the dilemma of how to make yellow uPVC white again. You may be tempted several household cleaners, some of which are to be completely avoided at all costs. The offenders in particular:
Bleach may seem a sensible option for cleaning your yellowed uPVC. It usually turns things white, doesn’t it? Why shouldn’t it do the same job for your window frames?
Unfortunately, it’s just not that simple; bleach reacts with the PVC and it can turn a horrible shade of brown. If you do use it, even if it’s diluted, you are likely to see awful results that can only be fixed replacing the entire window. DO NOT USE BLEACH ON UPVC WINDOWS!
Sandpaper may also seem a sensible option. If the top layer has yellowed, then surely all you need to do is scrape it away to reveal the whiteness beneath. Again, this is a huge misunderstanding of how uPVC works – the top glossy finished surface is created as the plastic is manufactured – the interior of the material is very different. It’s quite dull, and won’t repel water or stains in the same way as the glossy finish. If you sand your uPVC window, you’ll just ruin it. Simple.
How Do I Clean Yellow Upvc Windows?
Depending on the nature of the staining, you may have some luck with a more gentle cleaning solution. Ba wipes have been known to successfully lift away some stains, and they make a good first point of call if you already have access to them. General household cleaners like CiF should always be treated with some caution; make sure you check the bottle doesn’t contain any bleach!
There are numerous specially-formulated uPVC window cleaners on the market, which may restore new life to yellow UPVC windows. Even if you don’t get perfect results, you can at least be certain that you aren’t going to do any harm!
