This topic addresses mostly civilian casual and formal business clothing. Sometimes you have no choice but using them in survival or outdoors situations.

Trousers

The ideal would be Filson's 17oz whipcord pants but if I had to wear more commonly available civilian wool dress pants, what type of weaving and cloth is best for winter use? When I ask what are your thickest and warmest wool pants in men stores, they always suggest flannel wool. But I tend to think that flannel will not shed the snow as well as a wool serge (with visible diagonal ribs). I asked if they have wool serge but one answered that wool serge is lightweigt and meant for tropical weather and I know it's not true. He told me that now people go to their heated office from their heated car and heated house and so on and that people don't want heavier wool pants and that now it's the super numbers that sells (like super 100 etc). I found that most of the sales people talk through their hats and just try to sell what's in store that's all. I asked another what is tweed and she showed me houndstooth pants and told me that this is tweed.

Anyway my question is is it better a twill wool (serge, gabardine) pants in winter or wool flannel pants?

Button down shirts

Which one of the two common type of dress shirt Oxford/pinpoint and poplin/broadcloth is more wind resistant? Because I have in mind of wearing a shirt under a knit sweater so that it acts as a windshirt (and a civilian looking shirt) to help stop the wind when removing outer environmental layers.

Thanks
Frankie

very good questions--Quebec is much like Minnesota in
the winters and long and cold...i wore whipcord hunting
pants from LL Bean..the green ones with the leather trim
around the pocket--and a fairly heavy broadcloth shirt
also in the hunting style but still good for dressing up..
a Tattersal shirt with a tie is good for going out to dinner
but still warm..instead of trying to effect a "office"
look i went for the "lodge" look which was neat and still
kept you warm..now that i'm retired i just fall back on
flannel lined jeans and a LL Bean flannel shirt in the winter

I wore a wool gabardine uniform pant for about 20 years (until the department authorized a dac-wool blend), four of them in an area where we got snow measured in feet every winter, and the rest where the temp dropped into the teens often, but usually without any precipitation. I gotta tell you, if I had not been wearing good insulated undies I would have frozen. And those pants, in addition to shrinking when they dry, STINK when wet. I can not comment on any others, but I have read/heard that "forester wool pants" (not sure what those are, I have always assumed some type of USFS uniform pant, and I think that they are a whipcord) are great...