Experience with Klimaleichtblock KLB for masonry work?

Hello everyone,

for our shell construction, our architect specified 24cm calcium silicate bricks (+ETICS) for the exterior walls. Basically, as builders, we are also open to a monolithic construction method and would even prefer it if necessary. After various forum researches, there seem to be countless opinions about ETICS vs. monolithic and also about Poroton vs. aerated concrete (Ytong) etc. Therefore, the recommendation is probably to decide on what the shell builder offers and has experience with. Ultimately, the values count, especially the U-value, or how do you see it?

Now we have received a good offer for the shell construction. This shell builder offered climate lightweight blocks (KLB) for the walls. Based on the specification sheet, he initially specified 24cm stones as well but would also like to build 36.5 monolithic.

The climate lightweight block (KLB) was new to me until now. Therefore, I am grateful for opinions on this material.

Thanks and have a nice last pre-Christmas week

I have also recently dealt with this topic and settled on Poroton.

The three variants aerated concrete/Poroton/pumice (KLB) are all so close to each other that really only gut feeling can decide.

Everyone who lives in a house made of one of the variants says they are satisfied with it.. great climate... great soundproofing...

Price-wise, the differences were also not that big for me:

Poroton was €1100 more expensive than aerated concrete
Pumice was €2300 more expensive than aerated concrete
Material including labor for 150m² living space

The thermal values are also the same for the economical versions of the variants.

Even if I haven’t made the decision easier for you with this

My mantra is, take the stone your processor knows best. I live in a pumice area, here people have been building for decades happily with KLB as well as with Bisotherm. With the search terms "11ant WDVS", "Mantra", "Rotmaurer" or "Weißmaurer" you should find everything I have ever said about this running gag (or FAQ) topic here; my personal favorite would be the KLB (as said, equivalent to Bisotherm) monolithic.

Well, whether ETICS or monolithic should definitely be decided. Otherwise, the tenders are not comparable. With the 24 cm KS, the question is why it can’t be 17.5 cm, i.e. the price goes down. But you still have to add the ETICS on top. The 24 cm KLB executed monolithically will be too thin, i.e. a meaningful comparison would be e.g. the 36.5 cm KLB vs. 17.5 cm KS with ETICS.

The 24 cm KLB executed monolithically will be too thin, i.e. the meaningful comparison would be e.g. the 36.5 cm KLB vs. 17.5 KS with ETICS

No, I understood the OP or his shell builder to consider as a meaningful comparison 24 cm KLB plus ETICS (due to comparability with the other offer) against 36.5 cm monolithic (as the homeowner's preference). I share this view.