Posted: 18/04/2016 at 21:18
If you use silicone sealant it will have to be flexible enough so as not to stress the glass otherwise you're effectively 'gluing' it to the frame and then any thermal load etc will put strain on the glass. On aluminium frames the glazing strip not only seals but gives flexibility too. Also not all frames can use W clips as I found on mine, it has too large a gap between the retaining groove and the glass, however oddly the door has a different construction and I can use W clips here. So long as the greenhouse was in good condition before and was properly sat on a level base then there is no reason for it too be any different when rebuilt.