Found this Tyvek bivy for ~$30 and want to see if these are reasonable expectations for pairing it with my normal tarp. These are the use cases I'm thinking:

-packing it for rain, in case wind changes and blows rain through an A-frame or lean-to

-colder weather, partially for a smidge of extra warmth, and partially as a wind break (sometimes I can feel a strong wind through my sleeping bag)

-warm weather, when I want to open my sleeping bag but not be completely exposed to bugs

-possibly prevent dew wetting my sleeping bag when cowboy camping

I'm not planning on it being a primary shelter, just to supplement a tarp when needed. Tyvek is supposed to be breathable but I don't know to what extent-- I've heard of people making rain jackets with it. I've never seen the appeal of bivies but something this cheap and packable could be useful


also general bivy/tarp thread