ᐅ Exterior walls made of 24 cm hollow clay bricks: should I use external thermal insulation composite systems (ETICS) or Poroton T7 blocks?

Bookstar schrieb:

Unfilled blocks are bad for sound insulation. ETICS is used because of the plaster and installation.

That’s why filled bricks. The best of all.

I agree!

We have Poroton T9 17.5 cm (7 inches) with 16 cm (6 inches) ETICS. We can hear the neighbors talking when they are in the garden as if they were in the next room.
Inside (17.5 cm + 11.5 cm (7 inches + 4.5 inches) Poroton) you can hear everything between floors as well. Really bad.

Ötzi Ötztaler schrieb:

I have the Unipor W08 Plan with 36.5cm (about 14 inches) thickness, which are basically the same as the T8 Poroton blocks. So far, I’m very satisfied—no sound issues, or most of the noise comes through the windows anyway. Inside the house, it’s not overly noisy. The thick concrete ceiling provides good sound insulation between the floors.

If anything, I might have chosen 42.5cm (about 17 inches) for slightly better insulation, but that’s probably just wasted money.

The 42.5cm (about 17 inches) thickness doesn’t make a difference, not even for sound. I don’t understand why around here 95% of buildings are made that way. I wouldn’t choose the unfilled bricks anymore either. We debated for a long time—everyone we asked said filled blocks wouldn’t be necessary in rural areas like this, with no busy roads nearby.

In the next house, I will only use filled bricks, a concrete ceiling, and soundproof windows. I just wish there was better advice on this.

We visited a local glazier and asked about different glass options for our windows. The guy has been in the business for 50 years. He asked why we wanted new glass for new windows. We explained the existing ones only offer 32 dB sound insulation. He was surprised since they have triple glazing. After a call to the manufacturer, he had to admit we were right.

Thermal optimization concerns both the bricks and the windows, but unfortunately, this negatively affects soundproofing. As a builder, you naturally think you’re getting the best insulation blocks and the best triple-glazed windows, and everything will be fine—but that’s not the case.

Snowy36 schrieb:

In my next house, I’ll only use solid bricks, concrete ceilings, and soundproof windows... I wish there was better advice available...

That’s the problem—no one wants to admit it. Even some DIN standards only apply to single-family houses and are quite lenient.

Our prefab house looks good from the outside but is actually a disaster inside. We have an electrical system where if we ever rent it out, it would have to be to someone who is deaf. Our walls are double-layered with wood and drywall, and the doors are high-quality Grauthoff made of hollow-core chipboard.

If I ever build another house—which I doubt—I would use either sand-lime bricks with external thermal insulation composite systems (ETICS) or concrete. ETICS is not a problem if basic principles are followed during plastering. We have a Massa house nearby that already developed algae after 5 years, unlike neighboring houses.

Snowy36 schrieb:

When we asked, they said we wouldn’t need it filled here in the countryside ... no roads, etc.

So what noise bothers you then? I’m someone who, before controlled mechanical ventilation was common, often kept the window slightly open, and back then there were roads, playgrounds, and so on. It’s all a matter of sensitivity.

Lawn mowers, other construction sites, airplanes.

When you write "filled," do you mean perlite or mineral wool? Looking at the technical data for the perlite-filled 42.5cm (17 inches) bricks (T7/T8), the sound insulation value is not exactly impressive.

Mineral wool looks better, but it is also not significantly higher than that of an unfilled 24cm (9.5 inches) T14/T18 brick. Isn’t this value the decisive one, or what exactly is supposed to cause the "significant" difference?