I've done this several times. One note: if the wind catches the fabric stuff on the box spring in just the right way, eventually it will shred it - similar to how old flags wear out from perpetually being in the wind. That's only happened once though, but worth noting - placing a big tarp over the roof, then wrapping the box spring & mattress before strapping the whole thing down might be a good idea to protect it from such a problem & also protect them from any unforeseen circumstances.