double glazing maintenance – what’s this called and how do I replace it?

Sorry for the dull question, but I have some windows that need some attention. I replaced the seals on the insides of the opening windows recently, but now the outside bits look like they will be crumbling to dust soon and need to be replaced. They are about 20 years old if that makes a difference.

What’s this bit called? Seal doesn’t seem to be the right term. Is it just a case of pulling it out and pushing a new one in?

Thanks

It’s a gasket. I think you might have to remove the glazing bead to get at it. I am not a glazier….

There are many different sizes and profiles, it’s important that you use the correct one. In order to fit them, you will need to remove the beads followed by the glazing unit to gain access. A bit of silicone rubber lubricant will really help fitting new gaskets, they push fit into a groove in the frame.

edit, not a glazier but have carried out a lot of maintenance on UPVC windows over the years.

Someone on here posted this link ages ago to a company that does a sample pack of gaskets/seals so you can more easily find the right one you need.

Maybe it will be useful:

https://www.handlesandhinges.co.uk/double-glazing-seal-gasket-sample-pack/

If the beads are on the outside, and hence your unit is inherently insecure, then you might want to retrofit some security clips while it’s all apart.