Can't the fabric be made into shades? Shades can take many different shapes, some fairly drapey.

I tried this and it never looked right. The gap wasnt big enough for the curtains to hang behind the radiators so they billowed in front.

We want to put up curtains and have found a lovely fabric we like. We have 2 windows that are just above our radiators. Can be hang curtains to the floor (or at least behind the radiator). Neither radiator gets hot enough to burn.
The alternative is an expensive blinds job I guess and giving up the beloved fabric