ᐅ Wall construction of a country house

Hello,

Xinette schrieb:

The first suggestion was 17.5 Poroton plus insulation.
I think that is the cheapest construction method.

No. 17.5 plus ETICS (external thermal insulation composite system) is roughly as expensive as a comparable monolithic wall construction.

It is simply the easiest way to hide external settlement cracks from the viewer’s (homeowner’s) eye; thus avoiding discussions with homeowners. The cracks still occur, but they remain behind the ETICS.

Xinette schrieb:

From what I have read now, you should not build like that.

You should choose a wall construction that best matches your requirements for a single-family house. There is no single “ideal” brick or wall assembly; ultimately, it also depends on your financial capabilities and the targeted energy efficiency level.

Xinette schrieb:

I am naturally also interested in the experiences with walls insulated using Styrofoam.

If you have chemistry as a hobby, you will probably be able to follow the previous posts.

Regards, Bauexperte

Bauexperte schrieb:

No. 17.5 plus external thermal insulation composite system (ETICS) costs roughly the same as a comparable monolithic wall construction.

I would leave that open to debate... To achieve the same U-value with 17.5 Poroton plus, for example, 16cm (6 inches) EPS insulation, you would already need about 50cm (20 inches) Poroton. Whether that is comparable in price? That certainly varies regionally. You can, of course, use insulated Poroton blocks. However, then the insulation is inside the block rather than on the outside of the masonry...

It is simply the easiest way to hide external settlement cracks from the view of the client; thus avoiding discussions with homeowners. They still occur but remain behind the ETICS.

And above all, it is the easiest way to achieve high insulation values with thin walls. Not everyone likes narrow, arrow-slit-type windows. When using very thick walls, to get the same amount of natural light into the rooms, you need larger windows again. Larger windows, in turn, mean worse thermal performance. A vicious circle...

Hello,

DerBjoern schrieb:

I would leave that open... To achieve the same U-value as 17.5 Poroton plus, for example, 16cm EPS, you would need about 50cm Poroton.

No, that’s not necessary. You are forgetting to consider air as an “insulation material.” Generally, the more porous and therefore lighter the masonry is, the better its thermal insulation.

DerBjoern schrieb:

Is that comparable in cost? It definitely varies regionally.

That is probably only marginally the case since an entire work step is saved, which also reduces the time the scaffolding is needed.

DerBjoern schrieb:

You can of course use filled Poroton blocks. However, then the insulation is inside the block rather than on it...

I don’t see that as a problem; from my perspective, perlite or mineral wool are not comparable to EPS. However, currently, the filled brick is only necessary if the client wants to build ≤ Kfw 70 standard. From 2016 onwards, these blocks are expected to be used more frequently on construction sites.

Regards, Bauexperte

Bauexperte schrieb:
Hello,


No, it’s not necessary. You are forgetting to consider air as an insulating material. Generally, the more porous and therefore lighter the masonry is, the better its thermal insulation

17.5cm (7 inches) Poroton T7 + 16cm (6 inches) EPS with a thermal conductivity of 0.035 W/(m·K) => U-value: 0.138 W/m²K
49cm (19 inches) Poroton T7 => U-value: 0.14 W/m²K

This should only be true to a limited extent, since an entire work step is eliminated, which also reduces the scaffold erection time.

Not necessarily. A monolithic wall is also plastered separately. For an external thermal insulation composite system (ETICS), the painter doesn’t need much more time. The extra time the painter spends on ETICS is saved during masonry work. The difference in effort has only a minor impact on the scaffold’s standing time.

Okay, I’ve already understood quite a bit. Apparently, there isn’t one ideal building style. Still, I don’t feel very comfortable with styrofoam insulation. For some reason.

Second offer from the same construction company.
17.5 Poroton bricks plus mineral wool insulation, followed by brick veneer as a cavity wall. Financially, this is just within our budget.
Is this the better choice?
What about the mentioned settlement cracks? How can they be avoided???

Best regards, Xinette

If you like facing bricks, this is certainly a good solution!

Settlement cracks unfortunately cannot be entirely avoided. They will sooner or later appear especially in areas between masonry and drywall.