How to Replace Rubber Seal on uPVC Windows

If you can feel a draft but your windows and vents are closed and your window pane and window frame are intact, you should check the rubber seals. These are located on the windows that open and they work by compressing and closing the gap while the window is shut, and springing back out once it’s open. Over the years that springiness can go and the rubber seal may just have flattened to the point where it’s no longer functioning correctly, and letting a draft in.

Worn door and window seals can lead to higher heating bills as hot air escapes and cold enter’s, you’ll be spending more to keep your house warm. So if you’re looking to save money and soft the annoying draft out, follow the below steps.

Tip: All window rubber seals are not the same. You’ll need to match the specific profile of the old seal to know which new rubber seal to buy.  There are many different profiles for various types of frames and styles.

Steps To Replace Your uPVC Window Rubber Seal 

  1. First, you’ll need to open your window and go outside so you’re facing into your home.
  2. Locate the seal and carefully peel this away from the window. If this seal has been there for years and has worn down, it should peel off easily and without the use of tools.
  3. Clean the area and check for any mould patches where the plastic has melted together. It will block where the seal sits, so you’ll need to remove this for an airtight finish. 
  4. Once the area is clean and free of obstructions you can push the new rubber seals into the groves or lip where the old rubber seal used to be. You may need to cut the seal as you meet the corners. Make sure you cute these diagonally so that the two pieces of seal meet. If you can’t get them to completely join, add some silicone sealant on the corners. Remember to not close the window until that has dried out. 


What does uPVC stand for?

uPVC stands for Unplasticised Poly Vinyl Chloride. It is also known as vinyl windows. It’s a rigid material that is an extremely durable and long lasting form of PVC used within the building industry.

What is the difference between PVC and uPVC?

The main difference between PVC and uPVC is that uPVC does not contain phthalates or BPA. This means that it is a lot safer for transporting water and it also makes it fire-resistant.

Why is uPVC used for Windows?

uPVC is used for windows as it’s an ideal material for the frames. The rigid plastic has superior insulative qualities when compared to metal or wood.

Are Aluminium Windows better than uPVC?

Aluminium is stronger than uPVC which makes them a popular choice for windows that need a slimmer appearance and large glass pane. That means that aluminium windows can have a slimmer appearance, and a larger glass surface area due to the strength of the frames. However, uPVC performs better with it’s insulative properties.

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