ᐅ Condominium built to KfW 70 energy efficiency standard, uncertain regarding ventilation system choices

Good evening,

I have been looking for a ground-floor condominium for some time now, with 2–3 rooms and about 75 m² (807 sq ft) of living space. Tomorrow morning, I have a viewing appointment for a newly built property, scheduled for completion in June 2014.

Since this would be my first real estate purchase, I am a complete beginner when it comes to heating, ventilation, and controlled residential ventilation systems. I spent the whole weekend trying to educate myself, and the topic of ventilation technology keeps coming up.

According to the energy performance certificate of the condominium I will be viewing tomorrow, window ventilation is considered sufficient. However, based on various posts here in the forum, I am now quite uncertain.

I have a faint suspicion that the real estate agent will try to sell me the apartment without proper ventilation tomorrow.

I think that at the current construction stage (the roof including tiles is already installed), it is no longer possible to install a central exhaust system. What do you think about a decentralized solution, for example, the Viessmann Vitovent 200-d?

The room layout is as follows: living kitchen 29 m² (312 sq ft), bedroom 14 m² (151 sq ft), office 11 m² (118 sq ft), bathroom 5 m² (54 sq ft), guest bathroom 2.5 m² (27 sq ft), hallway 7 m² (75 sq ft).

I would be very grateful for any help—after all, my first real estate purchase shouldn’t turn into a nightmare.

Hello,

Michael1250 schrieb:
...According to the energy performance certificate of the condominium I plan to visit tomorrow, window ventilation is sufficient. Due to various posts here in the forum, I am now quite uncertain...

The energy performance certificate has nothing to do with DIN 1946-6. According to its definition, window ventilation is an accepted form of ventilation.
The pros and cons of a controlled residential ventilation system have already been widely discussed here. Each person must weigh this for themselves.

Michael1250 schrieb:
...I have a slight suspicion that the real estate agent will try to make the apartment appealing even without ventilation...

This does not necessarily have to be a disadvantage in individual cases!
As always, the decisive factors are the specific conditions. For windowless rooms, DIN 18017-3 or the respective regional building regulations apply.
If a controlled residential ventilation system is installed, it should include heat recovery!

Best regards