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Attaching twin wall polycarbonate to a cold frame

Hi all, I’m going to top my newly built cold frame with 10mm twin wall polycarbonate, which will be screwed to a wood frame to form the lid.
To attach poly to frame I bought the fancy cushioned button fixings (left of pic 2) but they are expensive monsters at 40mm wide and need wider lid timber than is ideal.
Question is, can I use the smaller button screws (right of pic 2), which are only ever listed for use with corrugated polycarb rather than twin wall? The screws are the same length in either case. I don’t want to compromise the twin wall in future, but with no wind lift/structural integrity issues as it’s a ground-hugging cold frame the smaller style fixings are tempting. Anyone used them with twin wall polycarb for a cold frame or similar successfully?
Thanks, Johnny


To attach poly to frame I bought the fancy cushioned button fixings (left of pic 2) but they are expensive monsters at 40mm wide and need wider lid timber than is ideal.
Question is, can I use the smaller button screws (right of pic 2), which are only ever listed for use with corrugated polycarb rather than twin wall? The screws are the same length in either case. I don’t want to compromise the twin wall in future, but with no wind lift/structural integrity issues as it’s a ground-hugging cold frame the smaller style fixings are tempting. Anyone used them with twin wall polycarb for a cold frame or similar successfully?
Thanks, Johnny


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It's still fine after 2 years but I don't expect it to see 30.
I'd go with Bob's suggestion if you want longevity
Fingers crossed mine last as long as yours - I didn’t realise polycarbonate had been around that long.