Can you use a vapour retarder paint on the ceiling instead of using a poly vapour barrier?

Anwas Qwelten June 8, 2019Updated: Aug. 3, 2020

I saw in your wall video that you advise to use a vapour retarder paint along with an outside air barrier.  Can you do this for the ceiling as well, thereby taking out that possible weak spot where the vapour barrier joins in with your walls?

Responses (2)

Anwas Qwelten 3 years ago

Hi, thanks so much for the reply and great information.  My questions are for a new build (in BC).  I'm also wondering about doing the interior walls with a small gap between the exterior wall to be able to slide gypsum board in a continuous air barrier as you mentioned was an option in one of your posts.  If I do this, how do I nail the interior walls to the exterior walls?  Is the only connection going to be at the top plate (where I'm thinking of using a gusset to tie the plates together as this will decrease another possible air gap should the interior top plate overlaps the exterior wall)?

Again, thanks so much for your support.  I love what you guys are doing here.  Super inspiring