Semi-detached house - Built in 2000 - Is ventilation useful / necessary?

Hi everyone!

As already mentioned in another thread, we are currently renovating our "new" old semi-detached house built in 2000.


What will happen:
- Underfloor heating
- Core insulation
- Roller shutter box insulation
- very effective and thick roof insulation
- new heating system (decision still open)

My girlfriend and I are both working full-time. Therefore, we can ventilate continuously at night (not very efficient) and again in the evening.
During the day it is mostly not possible due to absence. Possibly a dog will be in the house again - then permanent ventilation would of course be a nice thing.

We can definitely do the installation ourselves.

However, we are very inexperienced with this. For cost reasons alone, we have possibly considered a decentralized ventilation system.
We would ventilate the bedroom, living room, and kitchen that way. The bathroom we would ventilate manually?

What do you think about this and what price range do these devices fall into?
Heat loss should of course be avoided.

Thanks a lot
Tobias

You should have your semi-detached house looked at by an energy consultant - I think the modernizations you are planning should be considered as a whole. Which measures are necessary, which ones are optional. What is truly effective? Does your Vitodens already need to be replaced? I mean: we are talking about a house from the year 2000 - and not from the 50s :rolleyes:

Good evening and thank you for your feedback. Where can we find an independent and good energy consultant? They should be product-independent.

The Vitodens 300W from Viessmann is just an idea from us, since the current heating system is already 14 years old, has been little maintained and is therefore also defective. By installing a new heating system + insulation + ventilation, all of this could be coordinated at once and would certainly be worthwhile overall.

How can you recognize a good energy consultant?

Regards -Tobias

Evening and thanks for your feedback. Where do we get an independent and good energy consultant? They should be product-independent.

You, I don't know. I'm just a well-read home builder myself. Maybe from your gas supplier, Google, or consumer protection? I only know this: I would prefer to do without all this ventilation technology if it were still possible nowadays. Unfortunately, the regulations are so strict in new builds. With a used property, you have a bit more freedom... when I still had our detached house from the 70s, I was aware of the disadvantages but also the advantages of drafty windows ;) I mean to say: with a house from this millennium, it’s questionable whether it’s worth it...