HelpfulGardener.com

I have a problem with the windows of my greenhouse...
There is a thin layer of silicone on the windows of my greenhouse.
It makes it impossible to add a layer of chalk to protect against the burning sun.
The chalk does not stick on the windows.
Is there something I can wash the windows with, to remove the silicone?
It's a very thin, invisible layer.

You might use a shade cloth.

Denatured alcohol, nail polish remover, or maybe even plain white vinegar should remove the silicone film.

Try lighter fluid . I clean all kinds of glue off my hands with it and it evaporates quick!

Apparently, it's not a layer of silicone.
It's a coating which protects the glass against uv, erosion...
It has a very high surface-tension which makes it impossible for paint or silicone to stick on it.

Any idea how I can remove such a coating?
I'll try rubbing it with plain vinegar...you never know.
Can it harm the glass?

Vinegar cannot harm glass; it's what people used to use to wash windows with, before windex and everyone convinced us that synthetics were better.

But this coating was put on to protect your glass. Maybe it isn't a good thing to remove it? Tom is right there are other ways than the chalk to provide shade when you need it.

The problem is that I have tomatoes and melons in my greenhouse which I fasten at the ceiling with a rope.
I also let them grow along the ceiling.
So a shade cloth inside is very unhandy.
I don't know if it works outside...it rains a lot where I live.

The coating is something some companies put on the glass to 'upgrade' the glass, to make it more expensive I think.
Most greenhouses don't have a coating like that.
The company where I bought the greenhouse, was surprised when I told them.

If the stuff is just too slick for paint or whatever to stick to, would it help just to lightly sand it, rough up the surface. Then your shade coating might be able to adhere better?

Anyway the same solvents that were recommended for the silicone may work on whatever it really is.