Number of supply and exhaust airflows in residential ventilation

Hello,
our ventilation system for our house is currently being planned. Do the same number of supply air vents as exhaust air vents need to be planned?
Is there a guideline for how many supply air vents are needed, for example one supply air vent per 30 cubic meters of room?
What about the dressing room and the hallway downstairs and upstairs?

Best regards
Sabine

Do you have to plan as many supply air valves as exhaust air valves?

No, but the total balance of the supplied and the extracted air volume must be correct.

Is there a guideline on how many supply air valves are needed, for example one supply air valve per 30 cubic meters of room?

I don't know that, in any case there are certain maximum volume flows per valve. The required volume flow results from the desired air change rate (house volume in m³ divided by time, for example a complete exchange every two hours = m³/h or normalized to 1/h as change rate). Otherwise, you certainly need at least one valve for each supply air room and for each exhaust air room.

Depending on the valve, not more than 30 ... 35 m³/h (... 40 m³/h) of air should flow through one valve at nominal load. The higher the volume flow, the more pressure loss, the more noise and possibly drafts near the valve.

What about the dressing room and the hallway downstairs and upstairs?

Hallways are generally overflow areas (example: supply air in the children's room, exhaust air in the bathroom, the hallway is overflowed). Example dressing room: We have supply air in the bedroom and exhaust air in the adjacent dressing room.

Who is planning your system?

Our house construction company first created a plan for us. According to this, the living area receives 2x supply air and the open kitchen 1x exhaust air. The room is a total of 60m² in size; I don’t know if 2x supply air is enough. The hallway on the upper floor contains 1x exhaust air, but the hallway downstairs has no supply air. To ensure there is enough fresh air in the downstairs hallway, I think there should also be a supply air vent there; would that be possible? We have 4x exhaust air on the upper floor (bathroom, dressing room, kids’ bathroom, and hallway) but only 3x supply air (bedroom and one children’s room each).

Best regards
Sabine

Our hallways have no valves. It confuses me that you have exhaust air in the hallway upstairs, as I wonder how fresh air is supposed to get into the bathroom (and children's bathroom). Is there another toilet on the ground floor?

Best: upload floor plans and a list of the planned valves with indication of the nominal volume flows. Then we can talk about it.

In the upper floor there is supply air in the children's rooms and in the master bedroom. There is also a toilet on the ground floor. I don't have a plan with nominal volume flows, I would have to ask. How many supply air openings do you have in the living area? Our living-dining room has a volume of 127 cubic meters, is twice the supply air sufficient?

Best regards Sabine

I have no idea about nominal volume flows, I would have to ask.

When the planning is finished, this information must be available, otherwise the planning is not complete (You wrote above that planning is currently underway, so everything is still fine ...).

How many supply air openings do you have in the living room?

For our open living-dining-kitchen area, there are two supply air vents and one exhaust air vent.