How to replace the rubber seal on uPVC windows

Wondering how to replace the rubber seal on uPVC windows? Rubber window seals are attached to the outside edge of the window and the inside edge of the window frame. So when the window is closed, together, they create a seal, preventing draughts, moisture, and outside noise from penetrating.

They normally have a lifespan of around ten years. But once they become damaged, they can shrink or become mouldy, causing your double-glazing to be ineffective. As a result, you may notice draughts and cold coming in around your window, where the seals have flattened and are no longer able to do their job properly.

The good news is, window seals are relatively cost-effective and straightforward to replace. With the guidance in this post, you should be able to confidently replace the rubber seal on your windows to reduce draughts and outside noise.

How to replace the rubber seal on uPVC windows

uPVC window seal replacement is something that can be completed yourself if you’re an experienced DIYer with a little bit of know-how.

However, if you’re in any doubt, don’t hesitate to call in the professionals to ensure a high-quality, long-lasting finish.

Replacing window rubber seals: what you’ll need

Replacing window rubber seals doesn’t usually require any specialist tools. It can normally be done with just your fingers, pushing and clipping the replacement rubber seal into place.

The hardest part is often selecting the right type of replacement seals for your uPVC windows – there are many shapes and sizes to choose from. By ordering a sample pack of rubber seals, you can try each type of seal in your window before selecting the perfect fit for your double glazing.

The only ‘tool’ you’ll need is a pair of scissors or a utility knife to cut the seal to size when you come to complete the job.

How to replace window seals: step-by-step

There are two parts to replacing uPVC window seals: the seals on the frame and those on the window itself.

On a standard square or rectangular window you’ll need to replace the seals around all four sides: to the left, right, top, and bottom.

Once replaced, the seals will cushion against each other with the window shut, eliminating cold draughts.

Step one

Starting with the window frame, first, take a photograph or make a mental note of the way your existing rubber seal sits within the frame.

Step two

Next, gently prise the current rubber seal away from the bottom of the window frame, starting at one end. Keep this piece of seal to help measure up your replacement uPVC window seals. It’s recommended to cut slightly longer as you can always trim it down if needed.

Step three

Take the replacement uPVC window seal and push and clip it into place, making sure it is the correct way around as per the positioning of the original seal.

Step four

Repeat steps two and three for the remaining sides of the window frame (right, top, and left) and then for each of the four sides of the seal on the window itself – tackling one side at a time.

Step five

Sit back and admire your handiwork! You’ve successfully replaced your window seals and can enjoy reduced energy bills and less outside noise as a result.

Related content: Want to spruce up the look of your uPVC windows? Check out our guide to cleaning uPVC window frames.

Call in the experts for uPVC window seal replacement

While replacing rubber seals for uPVC windows is relatively straightforward, it is a time-consuming task. It also carries an element of risk if you’re working on windows that cannot be accessed from ground level.

An experienced window fitter will complete uPVC window seal replacement quickly and efficiently. To find a trusted and reliable fitter in your area, simply add your postcode to the search box below.