Our slab was poured some time ago by a construction company, unfortunately, the final result was "so-so" with 1cm differences in some places, which means extra expense in the form of self-leveling compound when the house is completely sealed. Anyway, our external walls consist of EPS blocks from Jackon (Thermomur 350) and now they need to go up. For those not familiar, these are blocks that are stacked on each other, just like Lego, they are hollow and filled with concrete, resulting in concrete walls with very good insulation.
Since the slab is uneven, the carpenter suggested we use QuickFix spacer plates of varying thicknesses under the blocks to achieve a straight line all around (checked with a ground laser). Because there will be an air gap between the slab and the underside of the blocks due to the spacer plates, the suggestion is to spray foam sealant into the space between the lower part of the blocks and the slab to seal the gap so the concrete doesn't pour out during casting and to avoid thermal bridging. Of course, one must be extra careful as we only want foam under the EPS on both sides and not in the middle where the concrete will be.
Is this approach correct, or are there better solutions? I obviously want the best possible result and do not choose solutions based on price tag. We have already gone around with a concrete grinder on the worst spots, it's many square meters with a lot of rebar protruding, making it difficult to achieve a completely level surface.
As for foam against the concrete, I was thinking of buying PURPRO construction foam from Relekta, is that the best option for us?
(image from Jackon)
Since the slab is uneven, the carpenter suggested we use QuickFix spacer plates of varying thicknesses under the blocks to achieve a straight line all around (checked with a ground laser). Because there will be an air gap between the slab and the underside of the blocks due to the spacer plates, the suggestion is to spray foam sealant into the space between the lower part of the blocks and the slab to seal the gap so the concrete doesn't pour out during casting and to avoid thermal bridging. Of course, one must be extra careful as we only want foam under the EPS on both sides and not in the middle where the concrete will be.
Is this approach correct, or are there better solutions? I obviously want the best possible result and do not choose solutions based on price tag. We have already gone around with a concrete grinder on the worst spots, it's many square meters with a lot of rebar protruding, making it difficult to achieve a completely level surface.
As for foam against the concrete, I was thinking of buying PURPRO construction foam from Relekta, is that the best option for us?
(image from Jackon)
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A spontaneous thought is to attach the blocks to the slab with mortar to be able to level them. But maybe that would create thermal bridges?
We've considered that idea, but I think it would create a thermal bridge since both the walls and the edge elements are insulated.A Emil_K said: