Replies

1. Expert Member
   MALCOLM TAYLOR | Jul 10, 2021 06:30pm | #1

   andy,

   The primary water control layer will be the cladding, The secondary layer, which I suspect will be behind rain-screen strapping, can be either a conventional WRB or the wood fibre insulation itself.

1. 
   andyfrog | Sep 14, 2021 03:48pm | #2

   Interesting, thanks!

   Do you know why in the video linked below, they chose to use a fully adhered membrane on the Gutex?

   Isn't it a bit overkill?

   https://youtu.be/hF19UqmBvRs?list=PL79udthqWDAe-7q96bNXf6R-8GNNG_3vO

1. 
   Jon_R | Sep 14, 2021 04:17pm | #3

   A fully adhered WRB can be a good exterior air barrier. And while it may be overkill for this, it is more resistant to water penetration.

1. 
   andyfrog | Sep 15, 2021 03:20am | #4

   Yes, the fully adhered WRB is a good air barrier--however, they specifically chose airtight sheathing as well (Finsa Superpan Vapourstop), which they also painstakingly taped. So I guess I'm a little confused when comparing it to Ben Bogie's assembly.

1. 
   Jon_R | Sep 15, 2021 10:47am | #5

   Note that interior and exterior air barriers are not equivalent and there is benefit to having both.

   Ben's house apparently uses a mostly interior side barrier, which in a cool or cold climate is superior to the just the exterior side.

2. 
   Jon_R | Sep 15, 2021 11:11am | #6

   If anyone is interested in more details about the roof:

   https://www.youtube.com/watch?v=JCZ5-vJdNfE

   I think the walls and roof are innovative and well thought out. Less clear is if
   wood fiber board insulation is cost effective and the assemblies are IRC complaint. For example R806.1 requires "cross ventilation for each separate space". As I see it, the roof cellulose is in a space with no ventilation.