Tyvek is a brand of flashspun high-density polyethylene fibers, a synthetic material; the name is a registered trademark of [DuPont](http://www.dupont.co.uk/). The material is very strong; it is difficult to tear but can easily be cut with scissors or a knife. Water vapor can pass through Tyvek, but ...
When buying Tyvek online, there appear to be a myriad of options and numbers. Which numbers are suitable for making a tent footprint? Known numbers: 1443R, 1622E, 10G, 10GX, 1460, RV, 14M... (may ...
Tyvek is labeled as "water resistant" and not "water proof", but I'd really love to know how much is the fabric resistant to water in practice. Some people built tarps or even tents out of it, but I ...