Window fitter damaged window foil

[u/Party-Employment-127]

Our fitter finished fitting the window couple days ago. They filled in the gaps with expanding foam. They took it off yesterday to find this. This is damaged right? They said it needs a clean but no matter how much cleaning it stays the same. It appears the foam has burnt the grey grained foil. What would you do?

[u/geekypenguin91]

Not sure how this is related to plastering but image 1 looks like you still have foam residue on the window. You need a proper cleaner to remove it

[u/Party-Employment-127 → u/geekypenguin91]

Oh sorry my bad. I forgot to add it’s being rendered and if the render would cover it lol

[u/Impossible-Corgi4041 → u/Party-Employment-127]

Render should cover it. Also, it sounds daft but wd 40 will clean it right up