House Wrap Question
 

I have felt/tar paper wrapped around my house right now. Can I wrap Tyvek over top of the tar paper or do I have to remove the tar paper first.

I am concerned that the house will not release moisture to the Tyvek right if the old tar paper is left on the house.

Ideas, knowledge in this area please. Thanks.

You're right in your thinking. I would really recommend removing the felt paper if you're going to install Tyvek. You don't want two moisture barriers on the same plane.

Download, print and follow Tyvek's installation instructions to the letter. Be sure to pay close attention to window openings, door openings, and seams. Be sure to use Tyvek tape to seal the seams up as well.

I would choose paper first, Typar second, Tyvek last. Paper does leak when saturated but the water behind it wicks to the outside, unlike the others. http://www.umass.edu/bmatwt/publicat..._barriers.html http://www.typar.com/pdfs/Typar_vs_Tyvek.pdf

Be safe, G

Thanks for the replies. I was thinking it would be better to remove the old barrier first but needed some confirmation.

The Typar does sound like the better product after reviewing the performance stats between the two. However, how expensive is it and how hard is it to come by?

They have it at my lumberyard. Try your local ones. Or, ask on their web site, or Google it.
Be safe, G

We never see Typar in this area. Not sure why. I can say that Tyvek is an incredible product and I'd happily put it on my house.

Around here if you use felt & then side w/wood shingles the wood shingles turn dark
If you use Tyvek your shingles look newer longer

Interesting, Dave. How many times have you seen that?

Be safe, G

Menards handles Typar HERE!!!