* the size of the corridor between the main room and the matching room. In most cases, it is appropriate to design the corridor size of the main room and the auxiliary room as **80 cm * *, but the specific size can be determined according to the actual situation.
* The distance between the principal room and the matching room. If the homestead area is relatively spacious, the distance between the main house and the allocation room can be kept at about * * 1m ~ 2m * *, which can ensure the lighting and ventilation effect of the main house and allocation room.
In addition, the air duct size of self-built houses is also affected by local policies, land area and other factors, and needs to be selected according to the actual situation.