I've never heard of it cracking. but then it isn't cold
for long where I live.
in the title you say sheetrock vs pine planking.
pine planking has lots of cracks for air to enter,
so it would be difficult to heat and cool even
for short periods.
sheetrock is 4'x8'sheets and the leakage areas would
be cutouts and seams. as the seams are taped and floated
sheetrock has less air leakage by the simple fact that it is a sheet good.
my clients that insist on beadboard ceilings or walls
are advised to put a backing behind it to stop the air leakage. usually sheetrock.

just info.

best of luck

I think sheetrock is absolutely fine.

By your title, I am assumming you are at/near a beach. For most of the US, that means it isn't really that cold. But you could be talking a beach on the UP of MI.

You might want to clarify what you consider cold.

We have a beach house that we heat a little to avoid having to winterize. Mostly set at 50, it probably runs a few nights a season.

Thanks for the helpful information...yes, it can get below freezing for part of the winter. We're conserned with the potential of the seams cracking due to the shrinkage of the wood behind the Sheetrock. Yes, this is a beach house in new York so it can get cold.

Code requires sheetrock underneath wood clad walls as a measure of fire prevention. So, even if you want to do plank walls, they will need drywall first. As long as there is no moisture intrusion, sheetrocked walls will be perfectly fine.