I have worn Tyvek suits while doing attic insulation work. Granted, the situation was hot, but if the garment vented any moisture, I couldn't sense it. It was more-or-less like being in a plastic bag in those high temps.
Now, if I was to wear a tyvek suit in the cold, maybe it would vent better. Maybe not, and I would get soaked and subject to hypothermia.
Venting moisture for a house clad in Tyvek is a lot different for a person venting body moisture, I'm thinking. If Tyvek vented moisture well, we would be wearing Tyvek instead of Gore-Tex.
Not to mention the stuff is pretty noisy/crinkly, and the stuff tears easily. Can't paint/dye tyvekl either.
AFAIK, the jury's still out on Tyvek outer garments, but I have never seen any Mil or major police using Tyvek winter outer garments. Maybe I
I have missed something.
It might be OK in a static, wet, snow/rain environment, but there are a lot of better, more versatile alternatives. Granted these alternatives cost more, but their versatility is much greater also..