Controlled residential ventilation in the basement, outside air through the roof

Hello everyone,

we are currently in the final phase of planning our house with a basement apartment (KFW40+).

We definitely want a controlled residential ventilation system, but we would prefer not to have an intake chimney in the garden, so the idea came up to draw the outside air through the roof ([Dachgeschoss ist ausserhalb der Thermischen Hülle, und nur mit 60mm Holzweichfaser gedämmt]).
Exhaust air then through a light well.

Is there anything speaking against this idea? Apart from the fact that my outside air path is significantly longer than my exhaust air?

Thanks and greetings

I'll jump on that. Similar idea/problem for me as well, but still without a solution...

We have the fresh air intake located on the carport. It works perfectly fine so far. Occasionally, we have slight odor problems when the neighbors have their fireplace on. However, this can also be smelled when you open a window on the ground floor; I assume it doesn't make much difference where the fresh air intake is located. (?)

I would only implement this over a light well if it is absolutely protected from water. If during a heavy rain event the mess runs in there, you will only have had a controlled residential ventilation system for a short time.

If I could do it again, I would use such an intake pipe. Then preferably in the front yard/street side and possibly plant it away.

Reason: with the fresh air you also attract small animals (mosquitoes, spiders, etc). In such a pipe you can very easily and accessibly install a weather-protected pre-filter. Not on the roof, plus long piping, and besides that you also risk drawing in hot air in summer there.

Ok, I hadn’t considered that point yet.

Since the technical room is relatively central, I would then have to lay the line about 10m underground to get around the corner of the house; you could then also suck relatively well there (it would be in the northwest), and avoid a short circuit 100%. However, I would still need a condensate drain.

I would only realize that via a light well if it is absolutely protected from water. If the mess runs in there during a heavy rain event, you’ve only had controlled residential ventilation for a short time.

That should not be a problem, since the outlet is planned relatively high up in the light well; if the water rises that high, controlled residential ventilation is my smallest problem.