ᐅ Poroton T12 bricks for exterior walls

I had actually planned to include the unfilled Unipor W08 planer bricks in the construction specifications. The W08 Coriso costs about 40% less in the price list than the 36.5cm (14 inch) planer bricks. I originally did not want insulated blocks, but now I’m really starting to doubt... Maybe larger buyers get completely different prices and, in that specific case, the planer bricks could still be cheaper than the insulated ones? Very unclear.

I would guess that because of the larger chambers, less clay, and more wool, these are more cost-effective.

We currently only have the foundation slab completed, with 6cm (2.4 inches) insulation on the underside. Masonry work with plan T12 Poroton is scheduled for January. Before Christmas, I inquired about the thermal protection certificate and was told it will be handed over to us after completion. Is this procedure correct?

Shouldn’t the energy-saving regulation calculation be available beforehand? In any case, we were always informed that changes are possible as long as they do not affect the structural stability or the energy-saving regulation. The building permit / planning permission has already been applied for, and construction approval (green light in BW) has been granted.

Is there a chance, if the T12 bricks have not yet been ordered, to upgrade to a higher-quality brick since manufacturers are phasing out these “old bricks” to promote newer ones? Are there any experiences with whether general contractors (GCs) are open to such changes?

Asking questions doesn’t cost anything... How are the other exterior surfaces of the house constructed? Insulation below or above the foundation slab? Insulation of the top floor ceiling or roof insulation? U-value of the windows?

Hausbauer schrieb:

Questions don't cost anything... How are the remaining exterior surfaces of the house constructed? Insulation below/above the foundation slab? Insulation of the top floor ceiling or roof insulation? U-value of the windows?

We are building according to the 2016 Energy Saving Ordinance.
Under foundation slab: 6cm (2.4 inches) insulation.
Above foundation slab: 7cm (2.8 inches) insulation.
Perimeter insulation: 6cm (2.4 inches).

Masonry 36.5cm (14.4 inches) T12 Poroton blocks.
Windows: Ug 0.70 W/m²K (U-factor 0.12 Btu/(ft²·h·°F)).
Top floor ceiling insulation: Mineral wool, thermal conductivity 0.035 W/(m·K), 200mm (7.9 inches).

This all sounds more or less like standard new build quality, except for the masonry. You should ask about the price difference for better insulating masonry; maybe the general contractor doesn’t charge exorbitant prices. You won’t achieve unrealistically high energy savings by improving the U-value from 0.3 to, say, 0.22, but in your position, I would consider paying a few extra euros. Are you heating with a heat pump or gas? Paying attention to proper design of the underfloor heating and correct setting of the heating system can often save as much on energy costs as better U-values of the building envelope.