Yes, upper entrance is good even here but now one ventilate in winter via cover edges. Are you not able to make a ventilation hole in front wall?
Guys are mad. When we talk about upper entrance, most of guys say that it makes "chimney effect". The hole diameter is 1,5 cm. Then you put match sticks and no talk about "chimney effect"
YOu know that even in Finland night is the coldest part of day. Every night air moisture goes to 100% or to 90%
What is the difference with your "climate" and our "climate".
Out door moisture is about 50% when sun shines. Then in boath country it rises to 100%
And what was the difference??????
When it rains, it rains and out moisture is 100%.
.
Come out from your tiny isle and see that there are same life outside your world..