My Shelter has shown zero condensation, probably because it is never heated, and if I run an engine inside, I always have one end open to allow lots of ventilation. A previous post alluded to using duckbill anchors. I heartily agree; my shelter has 12 such anchors, driven down about three feet, plus another 8 for the wind hold down straps. The bottom edge has turn buckle tighteners that tension the walls which are of very heavy guage UV stabilized polymer fabric with a reinforcing weave in between the doubled layers of the cover fabric. I elected to get the turnbuckle tighteners to make the edge tension uniform all the way along the wall. Then I placed four of my own manufactured corner braces made from 12' length of galvinized conduit tubing. the corner braces are anchored at the bottom of the door vertical corners and the inner upper vertical struts with clamp brackets and bolts. These diagonal braces prevent the thrust of the wind from causing the shelter to book fold under heavy snow loads (as my neighbors did) in any longitudinal wind forces. These diagonal longitudinal braces are not specified by the manufacturer, but they cveratinly should be, Because without them the structure would certainly have collapsed from repeated flexing of the welded joints of the skeleton frame (causing metal fatigue) My shelter easily withstands a 4 foot deep snow load, with rain on top of that. The shelter fabric will support three men walking on top without visible deformation. Of course the top is rounded, not flat. If you let hot exhaust to blow on the plastic, it WILL quickly melt, so you have to avoid that. In wind it is best to tightly close the curtain doors since they will scuff on their doubled) lower edges. There is another one of these SHELTER TECH buildings in an unshelterd area next to the St John River nearby. it is much bigger than mine is and has been standing undamaged fot eight years now, Through three hurricanes. THEY ARE THE BEST TEMPORARY SHELTERS THAT MONEY CAN BUY, IMO PRICEY YES, BUT YOU GET WHAT YOU PAY FOR...AND YOU CAN TRUST THEM TO STAY UP. (No, I am not a shill for shelter tech, just a guy that recognizes excellence and likes to have to do things only once)
Yes, you do have to follow the instructions carefully..and place foam tape at the wear points of the shelter where it stretches over the skeleton frame, Yes you do have place it on dead level ground with a decent thickness of fine crusher dust. One foot or more.
I reccommend buying a lot of extra duckbill anchors as well, one for every vertical part of the skeleton, and at least four wind straps also with duckbill anchors.
Duck bill anchors cannot be removed once driven into hard ground for three feet, not even with an FEL. It takes a ten pound sledge and a day of sweat to drive them in...but they STAY PUT in a hurricane, in fact in two hurricanes now. That is why I specified a tubular steel lower edge to mine. the streses are distributed evenly all along the wall, not at eyelet points.
My shelter is over-killed. That is a good idea. If you don't, then it could be a heck of a mess to set to rights, and cost away more than the extras I mentioned.
I never remove snow accummulations, usually it slides off, unless you already have freezing rain stuck to it