I am wondering if building experts have an opinion in the correct ordering of vapor and air barrier for a small 1 story house in Berkeley CA. We are planning a DER/Passive house retrofit and are figuring out where to locate the vapor and air barrier. One proposal is vapor barrier (let's say a good quality membrane) on the outside, keeps the moisture out and allows the house to dry out to the outside. In this setup, there is a continuous air barrier (lets say OSB with sufficient taping) on the inside, which helps to make the house quite airtight. In the middle would be loads of insulation. What are the issues with this setup? How can it be improved? Does this ordering make sense for Berkeley's climate. 

Thank you.

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Just asking questions and seeing what sticks is a poor way to obtain information. You should begin by reading the book linked below. It is used by many BPI and HERS trainers nationwide. It is a good overall introduction to many fundamental ideas. I would think it beneficial to your quest for information and there are many breadcrumb trails to follow as you read this book

Residential Energy By Dorsi Krigger http://www.srmi.biz/team-saturn/principals/john-krigger

The linked website below is filled with information. A great resource.

Building Science http://www.buildingscience.com/index_html

In your local area there are seminars you can attend. sign up for some building science classes

http://www.pge.com/pec/classes/

While you are in love with the Passive House Concept it is not the only system that exists. Look at these other systems below and understand what they have in common and what makes them different.

EEBA http://www.eeba.org/

Energy Star http://www.energystar.gov/?c=new_homes.hm_index

LEED http://www.usgbc.org/leed

The above is really only a start as most of us continue to follow breadcrumbs. We review what we think we already know, learn new concepts and try to improve our process.

And to answer your question I would say no but will not elaborate.

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