I purchased these pants and also a pair from Union Bay (Convertible Union Bay Youth Boys Cargo Pants/Shorts.)

The Columbias are VERY thin - like a light windbreaker material, but I don't think they would stop wind. As a matter of fact, they are see through. Plus, they have absolutely no give, so they aren't comfortable to move in, might alone hike. I returned and will buy more Union Bay (Much nicer quality and have stretch.)