WALLS
The material we used for the walls is a custom milled 1x8 poplar ship lap that was pre-primed on all faces before installing. We do this for two reasons. First, to help reduce moisture absorption during the humid part of the year which in turn keeps the wood more stable. Second, so when the boards are installed and gapped to 1/8" between each board, you won't see the raw wood.
The shiplap in this space has a 6 7/8" face with a 1/8 intentional gap between the individual boards. It's important to have your painter pre-prime all surfaces before assembling the boards on the wall and ceiling. This is done for two reasons. First to seal the wood making it less susepital to moisture migration, and second so that the gap doesn't read as raw unpainted wood.
One of the things to remember when you're using wood like this on the walls (and on the floors) is to acclimate the boards. This house is in FL and the boards were stacked, with spacers, in the air conditioning for a while to get them out of the humidity and reduce the moisture content (something you'll want to do with inexpensive pine). Doing this allowed the boards to shrink a bit before they went up, which kept the gaps from getting too wide after they were applied to the wall - and that kept the unpainted sides from being noticeable!
the paint used was Farrow and Ball Hauge Blue No. 30
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