uPVC window frames looking dingy or discolored? This quick and easy guide shows you how to clean them like new with minimal effort. Whether you’re tackling mold, dirt, or everyday buildup, these gentle cleaning methods restore the bright, clean look of your windows without harsh chemicals or damage.
PVC and PVCU are two types of vinyl widely used in construction due to their versatility and flexibility.
The two differ, as PVC is usually used to make siding and fences, whereas UPVC is used for window and door construction.
Due to its chemical composition, PVC is not used for window and door construction.
Some uPVC windows lose their luster over time due to dirt and grime build-up. However, they are relatively easy to clean.
Keep reading to learn how to clean your UPVC window frames.
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Cleaning uPVC windows is quite simple. Do not use abrasive sponges, scourers, or harsh chemicals like bleach or spirits.
Instead, when cleaning, simply use soap, water, vinegar, and a soft cloth. To keep your windows crystal clean, use some window cleaner and squeegee.
Alternatively, add some vinegar and clean with some old newspaper.
Top Mistakes to Avoid when Cleaning uPVC Window Frames.
Before jumping right into cleaning, you need to bear a few things in mind. When cleaning uPVC windows, it’s less about what you should do and more about what you should not do.
Certain chemicals and methods will cause irreparable damage to UPVC window frames, and thus caution is required.
Some chemicals will remove the waterproof and glossy coating and will lead to discoloration.
Here are some things you need to avoid when cleaning uPVC windows:
- Being too vigorous and applying too much pressure when cleaning.
- Use of bleach.
- Use of Cif or Jif cleaners as they are too abrasive for the material.
- Use of wire or iron wool, or scouring pads- again too abrasive.
- Nail varnish remover.
- WD40.
- White spirits.
How to Clean Inside of uPVC Window Frames.
Okay, let’s begin cleaning. Let’s start from the inside.
What you’ll need:
- Vacuum cleaner.
- Cloth.
- Water.
- Dish soap.
- Oil.
Follow these steps to clean the inside of your uPVC window frames:
- Open the windows as far as they go. There may be latches you can pull to allow them to extend further.
- Grab the vacuum cleaner, and attach the soft brush attachment—vacuum around the frame and hinges to collect dust, dirt, debris, and cobwebs.
- In a bucket, combine warm water with a few drops of dish soap.
- Dampen a cloth in the solution, and wipe the inside of the window frame.
- Add a few drops of multi-purpose oil to the hinges to keep them working properly and fully lubricated.

How to Clean the Outside of uPVC Window Frames.
The outside of the windows can get grimy quickly and can make your house look a little neglected.
Many of us neglect to clean the exterior of our homes, but it’s worth the effort to maintain your house, allow the materials to last longer, and keep your house looking clean.
What you’ll need:
- Cloth x 2.
- A hose or watering can.
- Bucket.
- Water.
- Dish soap.
- Window cleaner or vinegar.
- A squeegee.
Follow these steps to clean the outside of tour uPVC window frames:
- With a soft brush or cloth, remove any excess dirt, dust, and cobwebs. The more dirt you can remove while the window is dry, the easier this will be.
- If you have access to a whole, wet the entire frame and window to rinse away dirt. If you don’t have a hose, try pouring water from a bucket or watering can over the windows to rinse them instead.
- In a bucket of warm water, add a few drops of liquid dish soap or window cleaner (not the kind of stuff that comes out of a spray bottle). Stir to combine.
- Then, wet a soft cloth in the solution and wash the frames. Don’t apply too much pressure or use anything abrasive such as a scourer or wire wool.
- If you have a hose, rinse the windows. Otherwise, use a bucket or a watering can to rinse the windows and frames.
- Grab a squeegee, one that is dedicated to windows, and remove the excess water from the window. Start from the top at one side, move across and continue down. Continually wipe down the squeegee with a cloth.
- For an extra element of sparkle, spray the window down with a window cleaning spray, and rub it in a circular motion with a cloth. Note: do not spray the cleaner onto the frames. Alternatively, you can use distilled white vinegar. For this, in a bucket, combine ½ cup of white vinegar with 2 cups of warm water and a drop or two of dish soap. Apply a small amount of the solution to the window and rub it in a circular motion with an old newspaper.
Head to the link below to buy a professional window squeegee.
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If you don’t have access to a hose, watering cans can be super handy for cleaning windows.
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Distilled white vinegar is great for the kitchen but has a multitude of cleaning functions.
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Window cleaner:
[amazon box=”B01MUFTH05″ template=”vertical”]
How to Clean uPVC Window Sills.
Window sills need to be cleaned with a similar method to the rest of the window frame. Follow the steps below to clean the uPVC window sills:
- Add a few drops of dish soap or window cleaner to a bucket of warm water, and stir to combine.
- Wet a cloth with the solution and wash the sills.
- For stubborn dirt, wet the sills and leave the solution to get to work for a few minutes. Then, after 5- 15 minutes, wipe the sills.
How to Clean Mold Off uPVC Window Frames.
Mold is stubborn and annoying to clean from any area of your home. However, you should be able to tackle it using the following ingredients:
- White distilled vinegar.
- Spray bottle.
- A cloth.

Follow the steps below to clean mold off uPVC window frames:
- Add 1 cup of white vinegar to a spray bottle and 4 cups of hot water.
- Spray the uPVC liberally with the solution.
- Leave the solution to sit for a minimum of 10 minutes, but up to an hour.
- Wipe away the solution with a clean, dry cloth.
Can I use bleach on uPVC windows?
If you’re trying to restore the whiteness to your uPVC windows, you may be tempted to use some bleach. However, this should be avoided at all costs. Frustratingly, older uPVC windows can develop a yellow hue.
Bleach is usually great at dealing with yellow tinting, but not for uPVC. Bleach damages the surface, breaking down the compounds and discoloring them further. It can even turn brown, which is way worse.
Chemicals, such as bleach, strip the surface of uPVC and leave it looking matt, dull and darker. This damage is irreversible, so avoid the bleach, please.
To Summarize.
Cleaning uPVC windows is not difficult and doesn’t require the purchase of expensive, unique products. The main problem is that uPVC can react adversely with certain chemicals, so it’s a good idea to brush up on what not to do first.
Chemicals like bleach and white spirits can permanently strip the uPVC and damage the frame.
Additionally, using anything too abrasive to clean the windows will strip the top coat.
To clean uPVC windows, you only need a cloth, soap, water, newspaper, squeegee, and water. It’s really quite simple!
To help remove any mold, add some white vinegar, and you’ll have white, bright windows in no time.
