ᐅ Aerated concrete 42.5, thermal conductivity (lambda) 0.08 or 0.09 W/m·K

eddy8118 schrieb:

Additional costs are around 2000€ for our project. Good approach. Thanks!

If you include the lost living space, you’re easily over $2,000. Just consider what makes sense from your perspective.

Same here, I would also choose a thinner block (living space and cost). The disadvantages are not noticeable with high insulation and the minimal difference in living comfort.

Choose the 36.5, but definitely as a solid filled block. Consider sound insulation and how porous these things are. The hollow blocks they try to sell you today only benefit the construction company because the blocks are lighter and easier to work with!

I have 42.5 hollow myself.

Zaba12 schrieb:

If you include the lost living space, you’re easily looking at over 2,000 euros.
Just consider what makes sense from your perspective.

The 2,000 euros is the additional cost with the same wall thickness, only improved insulating properties.

Bookstar schrieb:

Go for the 36.5 cm (14.4 inches), but definitely as a filled block. Think about sound insulation and how porous these things are. That unfilled stuff they’re trying to sell you today only benefits the builder because the blocks are lighter and easier to work with!

I have 42.5 cm (16.7 inches) unfilled myself.

We’re talking about aerated concrete here, so filling is not really an option. I agree with you that unfilled Poroton is the cheapest. Our shell contractor offered Poroton as an alternative, which would have been 2,000 euros cheaper and he had it in stock, but we preferred to wait for the calcium silicate blocks to be delivered. Even if you think you won’t need to do anything for soundproofing on the outside, it becomes a problem at the interior walls—unless you live alone. My neighbor has 11–17 cm (4.3–6.7 inches) Poroton interior walls, which is really not acceptable. Now they’re trying to fix it somehow with solid wood doors.

guckuck2 schrieb:

The additional 2,000 euros is the extra cost for the same wall thickness but with improved insulating properties.

This concerns aerated concrete, so the question of filling doesn’t arise. I agree with you that unfilled porous clay blocks are the cheapest option. Our structural builder offered porous clay blocks as an alternative—they would have been 2,000 euros cheaper and were in stock—but we decided to wait for the calcium silicate brick delivery instead.

Even if you think you won’t do anything for soundproofing on the exterior, it will become an issue at the latest with the interior walls, especially if you don’t live alone. My neighbor has 11–17cm (4–7 inches) porous clay blocks as interior walls, which really doesn’t work at all. They’re now trying to compensate with solid wood doors.

I have all interior walls made of calcium silicate brick myself, but honestly, I don’t notice much difference compared to my neighbors’ houses, where many interior walls are made of porous clay blocks.

We also have 11cm (4.3 inches) and 17cm (6.7 inches) Poroton interior walls; you can’t hear anything through them... who knows what went wrong with the neighbor’s construction.