uPVC is the acronym for un-plasticized polyvinyl chloride and is essentially just PVC without any flexibility agents added to it.
It’s widely known for its shock absorption, durability, and strength. And that’s the reason you will commonly find it used in PVC doors, window frames, and pipes in earthquake-prone areas.
If, for any reason, your uPVC window was painted and you now want to remove the old dried paint, you must exercise caution in order to avoid harming the window. Also, the paint removal method or the stripping product you use should depend on the type of paint on the frames.
Removing Paint From uPVC Frames
If your uPVC window frames were painted with gloss paint, they should be reasonably easy to remove.
Unlike matte or flat finishes, gloss paint doesn’t stick well to plastic, so you can likely use the scraper by itself.
With a firm but not too vigorous movements, you may be able to remove some of the old dried paint. Be sure to attempt this first in a small area of the window to ensure you don’t scratch the PVC surface.
If the old gloss paint has already dried and is stubborn OR it isn’t a glossy finish, you can try some of these techniques to get the paint off…
1- Warm Water
If the PVC window were painted with any kind of matte emulsion paint, warm water would help soften it so that you can easily remove it.
To do this, first, soak a non-abrasive sponge in warm water and then use it to wet the paint. If the paint gets soft, it might be possible for you to wipe it off. If not, you can use the scraper to remove it carefully.
2- Paint Stripper
If neither of those steps gets the job done, you can use an everyday paint stripper instead to take the paint off.
Depending on the kind of paint stripping agent that you opt for, there is a chance that you will damage the PVC, so it’s essential for you to test it in a small area first to be sure this doesn’t happen. If it doesn’t, you are free to use it on the rest of the PVC frames.
3- Mineral Spirits
If you have light-colored or white vinyl window frames, there is a good chance that some of the pigment will stay there, which is difficult to remove.
Before anything else, try mineral spirits or paint thinner paired with an undyed cloth to get the pigment out. If this doesn’t work, use fine-grit sandpaper to sand the pigment away.
Removing Smears of Paint
Smeared paint commonly occurs if you accidentally drip paint on the window or frames and then rub something against it. This could also happen if you drop paint and then fail to wipe it clean.
You can carefully sand off any thick smeared paint from frames and casing using fine-grit paper.
Much like with specks from paint sprayers that have strayed, called over-spraying, using fine-grit sandpaper can easily remove it, but you need to use a light touch.
Removing Paint Sprayer and Roller Specks
Smaller paint specks that are made by vigorously using a roller can come off (after it dries) using a plastic putty knife or a scraper blade.
It’s important to avoid using razor blades because they can cut into the PVC itself. Also, because it’s difficult to maintain the right angle of a razor on the surface of vinyl, you may lose control over where you want to remove the paint.
For spray paint specks on any PVC, you can try to wipe it off straight away, if possible. If it has already dried, try sanding it off with fine-grit sandpaper as well.
But before you do that, remember that the sandpaper will make the surface of the PVC duller, so you’ll need to decide if it is more important that your window’s surface is preserved or if removing the paint takes priority.
Is Acetone Safe to Use On uPVC Window Casings?
Using any kind of nail polish remover (acetone), bleaches, acids, caustics, xylene, toluene, and other similar products aren’t safe for cleaning uPVC and vinyl windows.
Since these solvents can damage the surface of the uPVC, making it more susceptible to degradation and yellowing, I recommend using only soap and water, or a mild detergent, to clean your window casings.
If you need to remove something more stubborn, like paints or sticker adhesives, you may try cleaners such as Goo Gone, WD-40, rubbing alcohol, or denatured alcohol.
Always test these harsh cleaners in an inconspicuous area first to ensure they don’t damage the uPVC.
In case you aren’t very sure or do not want to damage your expensive window frames and casings, it’s best to consult a professional uPVC window cleaner. That’s a much safer and more reliable option.
The bottom line
It would seem that the best way to get dried gloss paint off UPVC window frames is by using warm soapy water.
However, if you have too stubborn paint to deal with, you could try using a few chemical-based cleaners (be careful not to harm yourself with this by wearing proper protection like gloves and a face mask).
Whatever method you choose, be patient and take your time – it’s worth getting the job done correctly so your window frames look as good as new.
Jack Luis is a semi-retired painter who loved painting his clients’ ideas on their walls.
He had worked as a painter for over a decade serving customers in areas such as Charleston, Mount Pleasant, Beaufort, and Georgetown, SC (South Carolina). Today in his free time, he likes to read and write about the newer techniques implemented in his profession. You may read more about him here or get in touch with him here.