What's the name of north-south connectivity? How to express it in letters?

North-south transparent apartment, H letter. Generally speaking, the north-south transparent apartment refers to a house, with both rooms with windows facing south and rooms with windows facing north, which can form a natural flow of air in the north-south direction in the house. North-South Permeability is called North-South Permeability, which is expressed by the letter H, and the apartment type is the structure and shape of the house. With the development of society, the improvement of people's living standards, and the difference of family life needs and economic conditions, it is ever-changing.