Hello,

I'm about to install some T&G poplar beadboard as a ceiling on my
exterior porch. Now the boards are inside @ 68 F and 30% RH, where
I've primed both faces and put the first finish coat on one face.
Outside we're been having an unusual cold spell for California, lows
30-35 F, highs 45-55 F, about 60% RH.

So two questions: do I want to let the board acclimate to the exterior
conditions prior to installation, and/or do I need to leave a small
gap between each board for future expansion? Obviously what I want to
avoid is installing the boards tightly when they are at the low end of
their expansion range, as then they may buckle when conditions bring
them to the high end of their expansion range.

Thanks, Wayne