I want to put up a triangular garden sail shade with one of the corners permanently attached to the uPVC frame of my conservatory. As the shade is tensioned with a turnbuckle, the fixing needs to be very robust and weatherproof. Should I use a pad eye screwed to timber which is stuck to the uPVC frame with adhesive (solvent-free 'gripfill'?), or is there a better method like special uPVC screws?
I don't know the age of your conservatory, and this isn't really relevant to your post - but drilling the conservatory will void and guarantee/warranty.