This may sound like kind of a silly question, but are snow pants designed to be worn over regular pants, or by themselves?

I only ask because I have a pair of thermal underwear to put on under my normal pants, but I'd like to get a shell of some sort to use over top of them (in conjunction with snow boots) to help serve as a water barrier when tromping around in shin high snow (I had the pleasure of experiencing winter in Minnesota instead of the more familiar Tennessee!)

I suppose it may vary with the particular brand, but in general, they are made kind of loose so that clothing can fit underneath. The ones I use have full side zippers, so that they can be donned and doffed without removing boots and crampons, etc. I believe a lot of people wear thick, insulating full length underwear so as to have maximum freedom of movement, as well as warmth.

Done it both ways depending on conditions outside. Alway had long johns under.

depends on the condition.

The intention of most snow pants is to be worn over the normal pants.

But I have been known to not include the normal pants due to the cotten factor in the normal pants thatI had on hand at the time.

I'm kinda like him. Usually if it's cold enough for snow pants I've got some long johns or running tights underneath. But I really never wear them other than skiing, when it's just those 2 layers. If I was camping, it'd probably be over whatever pants I wore to get to the base camp, when I'd don the snow pants.

I've always worn snow pants with something underneath them -- it was long johns when I was a kid, polypropylene baselayer nowadays, maybe sweat pants if I'm just running the snowthrower and can duck inside if I get wet and/or cold. I've learned the hard way not to wear jeans under snow pants.

Definitely designed to be worn over another layer -- polyester fleece pants, wool long underwear, et al. As previously stated, not heavy cotton, kinda defeats the purpose.

i got a pair of cheaper snow boarder pants that i pull on over my street clothes for the evening dog walks,at sub zero temps,and find they work great.nylon with some sort of poly insulation.i have no idea how they would work out for camping as they are sort of bulky.

The term "snow pants" covers a really broad range of stuff. Everthing from heavily insulated pants, to shell garments. What works best really depends on what you will be doing.

For emergency gear to carry in your vehicle, insulated pants that go over one's regular street clothes might be a good choice. Another option would be insulated coveralls, such as Carhartts. This sort of gear would be great to protect you while you dig your vehicle out, or put chains on, or wait for rescue. But it might be rather constricting and maybe too warm for active hiking or skiing.

For back country skiing I prefer shell type pants, made of gore tex or similar type wind and water proof fabric. I wear these over smart wool or polypro long underwear. I use the side zips to ventilate if I'm getting too warm. If it is really cold I substitute lightweight fleece (instead of long underwear) underneath the shell. This set up is very versatile for a wide range of temperature. It is also not too binding or constricting for skiing.

Whachever choice you make, it is important to size them to easily fit over any layers you might wear underneath. Remember, that each layer you add makes you bigger for the next layer on top! Before paying for expensive gear, it is always a good idea to try it on in the shop, over whatever layers you might wear underneath. My shell gear (jacket and pants) is all quite big, to give me plenty of room for layering. I'm not very stylish, but I'm comfortable in a wide range of conditions.

We do it both ways at our house. My son wears them over his clothes and I often do too by if we're going to be very active outside, I usually wear thermal longjohns underneath. Sometimes I'll double up on the thermals. I find them a little uncomfortable to wear with regular pants underneath, especially if hiking, skiing, snowshoeing, etc.