Introduction
Unplasticised polyvinyl chloride, commonly known as uPVC, is widely used for window frames across the UK. It is durable, weather resistant and requires very little maintenance. Many homeowners assume that once uPVC windows are installed, the colour cannot be changed. The good news is that you can paint uPVC windows if the correct preparation and products are used.
At Stroud Green Windows, we are often asked whether painting uPVC window frames is a good alternative to replacing them. For many properties, especially where the frames are still structurally sound, painting offers a practical and cost effective way to refresh the exterior. Whether you want to update white frames to anthracite grey, black or another modern shade, painting can transform the look of your home without the expense of a full replacement.
People usually choose to paint uPVC windows to match a new exterior colour scheme, modernise an older property or revive frames that look tired but remain in good condition. When carried out properly, painting can improve appearance and extend the lifespan of the frames.
What Type of Paint to Use
Choosing the correct paint is essential when you plan to paint uPVC windows. Standard interior wall paint is not suitable for plastic surfaces and will not adhere properly. Instead, you should select a paint specifically designed for plastic or uPVC.
uPVC paint is formulated to bond to smooth surfaces and withstand outdoor conditions. Acrylic based paints and specialist exterior satin finishes are popular options. These offer flexibility, which helps prevent cracking or peeling as the frames expand and contract with changes in temperature.
Some multi surface paints also work well on uPVC, provided they are labelled as suitable for exterior plastics. Always check the product specification before purchasing.
Primer is another important consideration. Some modern uPVC paints are self priming, meaning they do not require a separate primer. However, in many cases, applying a primer designed for plastic can improve adhesion and create a more durable finish. If you are making a significant colour change, such as painting dark brown frames white, a primer is usually recommended.
When selecting a finish, satin and eggshell are commonly chosen for window frames as they provide a smooth, modern look that is easy to clean. Gloss can also be used but may highlight surface imperfections.
Preparation Before Painting
Proper preparation is the key to success when you paint uPVC windows. Skipping this stage can lead to poor adhesion and peeling.
Begin by inspecting the frames carefully. Check for cracks, loose seals or damaged sections. Any repairs should be completed before painting.
Cleaning the frames thoroughly is essential. Use warm soapy water or a specialist uPVC cleaner to remove dirt, grease and residue. Pay close attention to corners and joints where grime can build up. Rinse with clean water and allow the surface to dry completely.
Next, sand the frames lightly using fine grit sandpaper. This process, often called keying, creates a slightly rough surface that helps the paint bond more effectively. You do not need to remove the existing finish entirely. A gentle abrasion is sufficient.
If there is any old silicone sealant that has deteriorated, it should be removed and replaced once painting is complete. Mask off the glass, seals and surrounding brickwork with painter’s tape to protect them from splashes.
Tools and Materials Needed
Before starting, gather all the necessary tools and materials. This will make the job smoother and more efficient.
You will need paint brushes for cutting in around edges and corners. Small foam rollers are useful for applying paint evenly across flat sections of the frame. If you are considering uPVC window spraying, ensure you have appropriate equipment and ventilation.
Other essential items include:
uPVC cleaner or mild detergent
Fine grit sandpaper suitable for plastics
Masking tape
Dust sheets or drop cloths
Primer if required
Exterior uPVC paint
Having everything ready before you begin helps avoid interruptions and ensures a consistent finish.
Step by Step Painting Guide
Step 1 Clean
Start by cleaning the window frames thoroughly. Remove all dust, grease and dirt. Allow the frames to dry fully before moving to the next stage.
Step 2 Sand
Lightly sand the surface to improve paint adhesion. Wipe away any sanding dust with a clean, damp cloth.
Step 3 Apply paint
If using primer, apply it first and allow it to dry according to the manufacturer’s instructions. Once dry, apply the first coat of your chosen uPVC paint using a brush or roller. Work in thin, even layers to avoid drips.
Step 4 Dry and second coat
Allow the first coat to dry completely before applying a second coat. A second layer improves coverage and durability. Follow the recommended drying times carefully to achieve the best results.
Drying Times and Number of Coats
When you paint uPVC windows, patience is important. Most exterior plastic paints require at least two coats for full coverage. In some cases, particularly when changing from a dark colour to a light one, three coats may be needed.
Drying time between coats typically ranges from one to four hours, depending on the product and weather conditions. Always check the instructions on the tin.
Full curing can take several days. During this period, avoid heavy cleaning or touching the frames excessively.
Tips and Best Practices
Choose a mild, dry day for painting. Ideal temperatures are usually between 10 and 20 degrees Celsius. Avoid painting in direct sunlight, as this can cause the paint to dry too quickly and result in brush marks.
Do not paint during heavy rain, strong wind or high humidity. These conditions can affect drying and adhesion.
Apply thin coats rather than one thick layer. Thin layers dry more evenly and reduce the risk of peeling.
Take your time and work carefully around edges and joints. A steady approach will deliver a more professional finish.
Common Mistakes to Avoid
One of the most common mistakes when people paint uPVC windows is skipping preparation. Failing to clean and sand the frames can lead to poor adhesion and flaking.
Using the wrong type of paint is another issue. Standard wall paint is not suitable for uPVC and will not withstand outdoor exposure.
Painting over grease or residue can prevent proper bonding. Always ensure the surface is completely clean and dry.
Rushing the process, particularly drying times, can compromise the final result. Allow each coat to dry fully before applying the next.
Frequently Asked Questions
Can all colours be used on uPVC windows
Most exterior uPVC paints are available in a wide range of colours, including white, grey and black. However, very dark colours may absorb more heat, which can cause expansion. Always check the manufacturer’s guidance.
Is primer needed for painting uPVC
Some specialist uPVC paints are self priming. In other cases, a primer designed for plastic improves durability and coverage, especially when changing colour significantly.
How long does paint on uPVC windows last
When applied correctly with proper preparation, paint on uPVC window frames can last several years. Regular maintenance and gentle cleaning will help prolong the finish.
Can you spray paint uPVC windows
Yes, uPVC window spraying can create a smooth finish. It requires suitable equipment and careful masking to protect surrounding areas.
Summary and Final Thoughts
So, can you paint uPVC windows? Yes, you can. With the right preparation, suitable materials and careful application, painting offers a practical way to update and refresh your window frames.
At Stroud Green Windows, we understand that not every homeowner wants to replace their windows immediately. If your frames are still in good condition, painting can be a cost effective option that enhances kerb appeal and modernises your property.
The key to success lies in proper cleaning, light sanding, using exterior grade uPVC paint and allowing adequate drying time. By following these steps, you can achieve a durable and attractive finish that transforms the appearance of your home.