Suppose the answerwas a bit terse, agree with Nutculet. My greenhouses are very strong and there is only a couple of inches of snow on the glass. I have knocked it off the Fruit cage netting and the Shade House which is netting and the Shade garden where the netting is getting a bit old and rather brittle.
Did shovel a lot of snow onto the beds in the Alpine house, save me having to water in there. Melts nice and slowly and gives the plants highly oxygenated water which is good for them.