I am considering material choices for the extension of the basement level. It's like an expansion from the house, and about half of the height is below ground.
I initially considered "regular" lecablock with insulation (cellular plastic) on the outside, but it seems to be a poor solution? These lecablocks were cheaper to purchase. Another option I am considering is Leca Isoblock. It is considerably more expensive...
I feel that I need help with the choice of materials for the exterior walls, both for those that are below and above ground. "Regular" lecablocks with external cellular plastic insulation, Leca Isoblock, or what?? How do you meet energy requirements regarding insulation, etc.?
One solution I am considering is building up the wall with "regular" lecablocks below ground with insulation on the outside of the exterior wall, but using, for example, Leca Isoblock for the part of the exterior wall that is above ground. Could this be a good solution?
I initially considered "regular" lecablock with insulation (cellular plastic) on the outside, but it seems to be a poor solution? These lecablocks were cheaper to purchase. Another option I am considering is Leca Isoblock. It is considerably more expensive...
I feel that I need help with the choice of materials for the exterior walls, both for those that are below and above ground. "Regular" lecablocks with external cellular plastic insulation, Leca Isoblock, or what?? How do you meet energy requirements regarding insulation, etc.?
One solution I am considering is building up the wall with "regular" lecablocks below ground with insulation on the outside of the exterior wall, but using, for example, Leca Isoblock for the part of the exterior wall that is above ground. Could this be a good solution?
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Well, I'm unsure how to achieve an "approved" U-value for the construction while keeping the price low. But on Weber's website (link below) I found Figure 3.8. A construction with Lecablock 250, external insulation with Serporoc (150), and external and internal plaster has a U-value of 0.18W/m2K. The wall is 42cm thick. Is this solution acceptable for my part?
http://www.weber.se/fileadmin/user_upload/pdf/leca/arbanv/leca-block-projektering.pdf
But the Swedish Energy Agency recommends a U-value of 0.13 for external walls...
http://www.energimyndigheten.se/Hushall/Bygga-nytt-hus/Klimatskal/
And there are legal requirements that the external wall does not exceed a U-value of 0.16
http://www.vattenfall.se/sv/husets-skal.htm
http://www.weber.se/fileadmin/user_upload/pdf/leca/arbanv/leca-block-projektering.pdf
But the Swedish Energy Agency recommends a U-value of 0.13 for external walls...
http://www.energimyndigheten.se/Hushall/Bygga-nytt-hus/Klimatskal/
And there are legal requirements that the external wall does not exceed a U-value of 0.16
http://www.vattenfall.se/sv/husets-skal.htm
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I am following Figure 3.8 in the document from Weber that is linked above. I am responsible for quality on the construction according to the old form of building permits, and therefore it is good to be aware of U-values and other factors. There are no legal requirements for 0.16 U-value. I don't understand why it stated that in the link to Vattenfall, as it only caused confusion..
We are building a split-level house and were advised to be cautious with isoleca below ground level. So we are using regular leca below ground and isoleca above, in a stepped formation. Below ground there will be 100+100 mm isodrän.
The bricklayer I had was rock solid... Heh, ahem. Then I saw similar advice here and there. I think the stability is significantly lower in isolecan. Check with the manufacturer if you're unsure.
We insulate with a thin (45) foam plastic on the inside of all the walls. It is done with consideration, though, since you generally want the insulation on the outside. No extra insulation above ground, as we have wooden walls on top whose facade should align.
We insulate with a thin (45) foam plastic on the inside of all the walls. It is done with consideration, though, since you generally want the insulation on the outside. No extra insulation above ground, as we have wooden walls on top whose facade should align.
If possible, try to get insulation on the outside of the wall above ground as well; in winter, it's the wall above ground that is most important to insulate, below ground it cannot get as cold as it can above ground.
Weber recommends regular leca with external insulation below ground and isoleca above ground according to their website. I don't understand why you think it would be a bad solution? The reason probably has to do with soil pressure.