I wouldn't make any holes in your upvc you'll cause problems and or regret it... I got round a similar problem by using suction pad hangers (local pound or thrift shop) and/or the cheap lightweight curtain rods that hang by means of a sticky pad backed bit of plastic with a metal hook on ( again local pound or thrift shop)..attach to the upvc or even the glass itself..pop some lightweight net or other lightweight fabric onto the rods and bobs your uncle..ps garden canes are every bit as effective as rods, but clean and dry them well first.
sally anne
November 2009
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