Leaving unfinished oak on a north facing wall?

[Co1]

I want to leave a set of external oak doors unfinished on a north facing wall. Obviously they won’t be as prone to UV damage, but is there any risk to them taking on too much moisture if they never see direct sunlight?
Thanks
Col

 

[woodieallen]

Have a look at existing wood facing North. Is it green with mould or moss ? If so then there’s your answer.

 

[Co1]

Good advice that, I’ll check. What if it is, does it mean it needs to be protected with something?