Decentralized controlled residential ventilation so expensive?

Hello everyone,

I have an offer for the installation of Inventer fans throughout the entire house. The house is a semi-detached house with about 130sqm of living space.

The costs amount to approximately €10,500 in total, which I already find very high. The semi-detached house consists of a basement (no fans are planned for this), ground floor, upper floor, and attic.

Ground floor: 2x iV14v, 1x iV Twin and 1x exhaust fan in WC/shower, separate control for ground floor
Upper floor: 3x iV14v and 1 exhaust fan in the bathroom
Attic: 2x iV14v

I believe that upper floor and attic have a common control - but I would have to check again.

Is the price okay or much too high? Would a central controlled residential ventilation with [WR] also be feasible at this price?

Please help - I really need support here... Thanks.

Regards Robert

Retrofit or new construction?

New construction! In just over a week, construction will begin. It is a Kfw70 house. Thank you.

I would rather opt for a central controlled residential ventilation system in new construction. Decentralized systems are generally intended more for retrofitting. I think a central system should also be included at that price. It requires many wall penetrations and I’m not sure if I would find that very appealing.

Does anyone possibly know a good ventilation engineer in the greater Cologne area? Thank you.

Just a quick note on the price. It is significantly too high. For a little more, we get a central controlled residential ventilation system with heat recovery - but designed for 300 sqm (Anlage Vallox 510SE)!