Hello dear community,
Although this topic has been discussed in several posts before, long-term experiences are missing here.
I am currently planning a 150 m² (1,615 sq ft) new build with a basement. We have now narrowed down our choice to two builders who differ fundamentally in their building materials.
The house is planned to be built without insulation, using a monolithic construction method. One builder wants to use aerated concrete or Poroton blocks (wall thickness 36.5 cm (14 inches)), while the other plans to use a solid precast wall made of expanded clay aggregate with a wall thickness of 41 cm (16 inches). We are now a bit uncertain because the thermal transmittance (U-value) given by the builders differs greatly: 0.21 W/m²K for Poroton and 2.2 W/m²K for expanded clay. Both assure us that the houses meet the KFW 55 standard.
I am unclear how the U-values can differ so much or whether other factors, such as the mortar used with Poroton, are included. The insulation in the attic and the windows (triple glazed) seem comparable in both cases. Are there any long-term experiences in this forum with solid walls made from expanded clay?
Can you tell me whether a similar energy balance for heating can be expected based on the KFW 55 standard?
Our concern is that with poor insulation and a heat pump, we might not achieve sufficient room heating or end up with very high heating costs due to additional electric heating rods.
Best regards,
Sven
Although this topic has been discussed in several posts before, long-term experiences are missing here.
I am currently planning a 150 m² (1,615 sq ft) new build with a basement. We have now narrowed down our choice to two builders who differ fundamentally in their building materials.
The house is planned to be built without insulation, using a monolithic construction method. One builder wants to use aerated concrete or Poroton blocks (wall thickness 36.5 cm (14 inches)), while the other plans to use a solid precast wall made of expanded clay aggregate with a wall thickness of 41 cm (16 inches). We are now a bit uncertain because the thermal transmittance (U-value) given by the builders differs greatly: 0.21 W/m²K for Poroton and 2.2 W/m²K for expanded clay. Both assure us that the houses meet the KFW 55 standard.
I am unclear how the U-values can differ so much or whether other factors, such as the mortar used with Poroton, are included. The insulation in the attic and the windows (triple glazed) seem comparable in both cases. Are there any long-term experiences in this forum with solid walls made from expanded clay?
Can you tell me whether a similar energy balance for heating can be expected based on the KFW 55 standard?
Our concern is that with poor insulation and a heat pump, we might not achieve sufficient room heating or end up with very high heating costs due to additional electric heating rods.
Best regards,
Sven
Nida35a schrieb:
According to the datasheet, it’s a very good block and will give you the bungalow of your dreams.
Have you already found your building supervisor?Not yet. We have an appointment tomorrow with the architect and the managing director of the general contractor. Hopefully, the building permit / planning permission application will be submitted within 2-3 weeks at the latest.
H
hauspeter22 Sep 2020 11:18Ybias78 schrieb:
This would be our brick. Does anyone have experience with it?We used this brick for a cavity wall with additional insulation and a facing brick. The house is still standing.
hauspeter schrieb:
We used this brick for a cavity wall construction with additional insulation and facing brick. The house is still standing. We are building without insulation and without facing brick. Inside, we are using lime-gypsum plaster. Outside, just plaster as well.
So, it is a type of stone that can be used for construction. With a thickness of 36.5cm (14 inches), it meets the energy standard adequately, but no more than that. The sound insulation rating is similar.
Don’t get me wrong, I just want to put the statement that this is a "very good stone" into perspective.
It all depends on what your requirements are.
Everything else becomes a matter of philosophy.
Don’t get me wrong, I just want to put the statement that this is a "very good stone" into perspective.
It all depends on what your requirements are.
Everything else becomes a matter of philosophy.
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