(Please, DON'T SHOUT. It hurts our ears with all the CAPITAL LETTERS, and stuff. It doesn't get you any better 'service' than if you used lower case lettering. In fact, it's been said that some folks will avoid a poster who shouts. It's just an etiquette 'thing'. I'm not trying to beat you up on this but there are a plethora of sources on this. For just one in a 1000, see One Source Of Netiquette.)
Moving right along ... Tyvek is an air filtration barrier; not a moisture barrier. Tar paper is more of a moisture barrier. (You may already know this but ...) If you don't get a satisfactory answer here, try The Cedar Bureau. They have e-mail.