> At what wind speed will the most storm worthy winter tent (that's packable) have
> it's fabric ripped apart?
Not a simple question. There are a number of obvious factors, and a number of less-obvious ones too.
Let's start by limiting the designs to be considered: serious geodesic domes with lots of poles, and tunnels. Pop-ups and tarps need not apply.
Obvious preliminary question: has the fabric suffered any UV degradation?
Examination of the remains of tents on the South Col of Everest shows the fabric in tatters, consistent with them shredding due to the UV degradation they get up there. Let's assume fairly new fabric.
A major factor is the detailed engineering design of the tent. If there are large unsupported fabric spans the tent shape will distort and collapse. If the poles form long unsupported spans they can buckle and collapse. Both of these factors are discussed in our series on Tunnel Tents.
I should not need to mention that all the poles must be fully sleeved in the fly. Designs where Velcro tapes and hooks etc are used simply do not survive. Tents where the inner has the poles and the fly is thrown over the top are total non-starters. They simply do not feature. Again, see our series on Tunnel Tents.
Then we come to guy ropes. We will ignore the 'free-standing' category here as irrelevant (that's me being polite). Guy ropes need to be placed on the tent with some consideration. Typically they are used to support the poles against the wind, so they need to be placed with some engineering knowledge. Some tents have guy ropes in the middle of fabric areas. Most (not all) designs with such guys are for mild weather only.
Guy ropes are no use without firm stakes in the ground. If a stake moves, you have trouble. I will add here that some tent designs need stakes not only on the guy ropes but also on the corners of the tent: where the poles hit the ground. Tunnel tents are critically dependent on the two upwind corner stakes: without those being rock-solid, big trouble.
Where you pitch the tent also matters. Any shelter helps; pitching in the middle of an open saddle (this may be spelt 'funnel') does not help. Me, I favour just downwind of a copse of trees. They slow the wind without creating turbulence.
A much less obvious factor is how tightly the tent is pitched. After UV degradation, the number one killer of tents is probably flapping. If the fly is loose, the flapping will eventually rip out the guys and shred the fabric. That is why I place so much emphasis on guy ropes and stakes.
That will do for now.
Cheers
.
