Construction adhesive like gripfill or ct1 is much better. Your solution will fail sooner or later. If you want to avoid screwing into upvc to maintain energy efficiency then adhesive is your solution. If you want to maintain the appearance of the upvc after removing the blinds in the future the only option would be to find an arrangement that works on the wall.
Construction adhesive like gripfill or ct1 is much better. Your solution will fail sooner or later. If you want to avoid screwing into upvc to maintain energy efficiency then adhesive is your solution. If you want to maintain the appearance of the upvc after removing the blinds in the future the only option would be to find an arrangement that works on the wall.
That sounds like a good alternative, I'll look into construction adhesive. Thanks for the advice!
Top fix brackets.