Replies

1. 
   AndyEngel | Apr 08, 2013 08:53am | #1

   Several reasons

   First, yellow pine responds eagerly to changes in humidity. It's also not particularly rot resistant. For these reasons alone, back (and end) priming are important. You don't want it to get wet from behind. As to acrylic paint allowing moisture to pass, that's true to some extent. There are limits though, and back priming should help to slow moisture movement and increase the odds of your surface paint sticking long term. Another factor is that yellow pine has a relatively high coefficient of expansion - That is, it moves a lot. Acrylic paint is flexible, but has its limits. Back priming should reduce moisture absorbtion and minimize the chances that the wood will out-stretch the paint.

1. 
   AndyEngel | Apr 08, 2013 08:55am | #2

   I should add...

   ... that I would back prime CVG cedar, as well. It's that important.