Controlled residential ventilation with heat recovery --- a confusing maze?

The general contractor did not insist here, but clearly stated that it is not necessarily needed (if you really ventilate well). However, in our case, no one is practically at home between about 7 a.m. and 4 p.m. That would be (new construction) rather unfavorable in the first years, since (boost) ventilation would of course not take place here.

First of all, a quite good statement from the general contractor, where one might suspect loyalty to the client.

Basically, one has to make a qualified statement as to whether natural infiltration plus window ventilation is sufficient to ensure moisture protection (FN). In very tightly built houses, one can almost assume that it does not, since it must be assumed that airing out 4 times or even more is at least necessary. A concrete calculation can provide an answer to this. With longer absence during the day, it is hardly possible to ventilate as often as required in the remaining time. Moreover, we humans tend to ventilate with our noses.

A calculation provides information about the amount of air available, the level of natural infiltration, whether a ventilation system is necessary, how the ventilation influences airing (how much air is exchanged in what time at which setting), and possibly energy consumption or savings, and perhaps also electricity consumption.

If a ventilation system is planned, it must be designed at least at the lowest setting for FN.

Even if this answer may no longer contribute to a decision or just conveys my view to you, I still wanted to leave this here for others at this point.