ᐅ Building Without a Ventilation System Using Porous Clay Blocks?

My system consumes 50W depending on the selected setting (I use the moderate setting). That amounts to 438 kWh per year. At 25 cents, that comes to €110. The filter costs about €60 (replaced 1-2 times per year).

The system costs from €7000.

I am glad that I chose a controlled residential ventilation system.

because only in this way can you maintain the air exchange rates necessary for the building’s structure.

No... as already mentioned, there are simpler, more affordable systems for this purpose, but they do not offer the comfort of a controlled residential ventilation system with heat recovery...

An exhaust air system plus window frame vents to provide basic ventilation and mold protection, combined with manual intermittent airing from time to time, would also be sufficient...

karliseppel schrieb:

In short: You won’t avoid an HVAC system if you want to build the house according to regulations. (I don’t think anyone realistically ventilates every two hours, even at night)

What nonsense. Many still confuse oxygen levels with humidity levels.

The core issue is not the oxygen content, but the humidity level. Oxygen lasts forever if ventilated twice.
More problematic is the humidity, especially in overly insulated houses,
which then make the occupants sick.

Often a humidifier helps here (about 200 euros, e.g., a mid-range device plus a few bottles of distilled water).
I have had one in my office for years now.

You can also over-isolate yourself into poverty or suffocation? A marketing gimmick, like thermal solar systems, which hardly bring effective added value.

I’ve researched this over the last few days. What is being sold is unbelievable.
I’d rather burn 2 to 3 cubic meters more hardwood briquettes in the stove each harsh winter.

OT:
Use a 36 cm (14 inches) brick for exterior walls. Perforation type A has a single hole cross-section of 2.5 cm² (0.4 in²). There are also perforation types B and C, but they are not recommended.

Often, a 60 mm (2.4 inches) hemp internal insulation makes more sense. External insulation, especially thick polystyrene panels, often cause condensation behind the insulation.
After 15 years, this usually leads to building damage and mold growth.

Better: a solid plaster on the 36 cm brick plus a high-quality exterior paint layer so the wall can still breathe.

I would currently not install an HVAC system. The filter technology is still in its infancy. I would increase the room height by 25 cm (10 inches) during construction to allow for a suspended ceiling and for possible future pipe installations.

@kamnik,
What you’re saying doesn’t make sense.
Please provide a source to support the connection between ventilation and oxygen supply.
DIN 1946-6 defines four ventilation operation levels – none of them is specifically for oxygen.
There is also a minimum hygienic air exchange rate, which is usually the basis for designing such systems.

Oxygen lasts forever if you ventilate twice.

So, does it last forever or only if you ventilate?
Even though oxygen supply through ventilation plays a minor role, it still can’t be denied.
The removal of moisture and CO₂ is far more important.

The real issue is that hardly anyone still thinks it’s necessary to have a proper ventilation concept developed (and paid for).
This is how such requirements can be demonstrated.

Better: proper plaster on the 36 cm (14 inch) wall plus high-quality exterior paint, so the wall can still breathe.

Now you’ve really gone too far with the idea of breathing walls...
Ask yourself what would actually be able to breathe if you place insulation on the interior side, which inevitably requires a vapor retarder for living spaces.

When building, I would set the ceiling height 25 cm (10 inches) higher because of suspended ceilings and future possibilities for pipe installation.

I’d like to do that too, if only the development plans from public authorities would finally allow it, so people wouldn’t have to pay for limited living space upstairs (knee wall, roof pitch, etc.).

-Knee wall

karliseppel schrieb:
@kamnik,
What you’re saying is nonsense.
Please provide sources showing a connection between ventilation and oxygen supply.
DIN 1946-6 specifies four ventilation operating modes – none of them is specifically for oxygen.
There is also a required minimum hygienic air exchange rate, which is usually the basis for designing such systems.

I don’t need any DIN standard for that.
Practical example: Windows are often opened wide because people feel there is a lack of oxygen. (common practice)
In reality, the volume is simply missing humidity, and that is the key difference.
Unfortunately, the industry and sales reps suggest otherwise by arguing: yes, opening windows consumes energy, etc.

In my opinion, that’s nonsense!
What’s harmful is the airtight insulation approach. I could post some expert reports here, but the moderator won’t allow it (probably because they represent certain companies), and the argument wouldn’t be welcome.

At the same time, they want to install an overpriced system in the house, which will be faulty or obsolete after 20 years; like a new investment. Planned obsolescence in terms of quality.

karliseppel schrieb:
So now – does it last forever or only if ventilated?
Even if oxygen supply through ventilation has a secondary role, it cannot be denied.
Removing humidity and CO2 is more important.

See my previous post; the suggestion for forced airtight insulation plus locked-in technology – amortized over 30 years, maybe?

Why are winemakers returning to clay pots buried in the Trieste hills?
Answer: They avoid all the constantly failing technology.

karliseppel schrieb:
The problem is mostly that hardly anyone considers it necessary
to have a proper ventilation concept developed (and paid for).
Because that is how such needs can be demonstrated.

Ventilation concept? We have lived in houses over 350 years old. The builders back then were no fools, and the building quality was hardly worse than today’s standards.
“Building standard” – what a buzzword; if I define Styrofoam insulation materials as building standard, that definitely rings alarm bells for me.

karliseppel schrieb:
Now you really go too far with “breathing walls”…
Ask yourself what is supposed to still “breathe” when you place insulation on the interior side
and therefore necessarily need a vapor barrier towards the living space.

They should look into wall claddings with Styrofoam materials and mold growth behind the facade insulation boards?

Vapor barriers mean mold growth. In new buildings, in renovated buildings, etc.
A well-known building inspector visits such residential buildings daily, where mold hangs in the corners because no air is reaching there anymore, and mold formation is inevitable.

karliseppel schrieb:
I would also like to, if only the zoning plans by public authorities
would finally take this into account and people wouldn’t have to pay for it with
restricted living space in the upper floor. (Knee wall, roof pitch, etc.)

-Knee wall

Zoning plans? Oh, please.
Just build, have the construction stopped, pay penalties, and that’s it. (It’s faster than applying for a separate building permit / planning permission.) Common practice.

Rarely have I read so much nonsense in one post.