ᐅ Poroton T9 unfilled or Poroton T8 with mineral wool insulation?

Hello, my project will start this summer and I need to choose a masonry block now. The options are Poroton T9 unfilled and T8 filled with mineral wool (additional cost 2500 €). My question is (I have done some research already): Are the unfilled blocks really much more prone to cracking than the filled ones? I have looked at them, and the webs are definitely much thicker. The mineral wool is packed very tightly, so I hope it will only shrink a little over the years.
Thank you for your help.

Best regards

Fridel

No, I haven’t. I think I will save some money over the years. However, it is more important to me that I do not have, or develop, any cracks in the masonry.

Hello,

fridolinmeier schrieb:
No, I haven’t. I think I will save up gradually over the years. However, it is more important to me that I don’t have cracks in the masonry, or develop any.

Cracks can always occur over time, regardless of the type of brick, because the house naturally settles. However, with careful planning of the foundation and site preparation, cracks can be minimized.

If you absolutely don’t want to see any cracks on the outside of the house, you need to build with ETICS (external thermal insulation composite system). Cracks may still form, but they will be hidden behind the insulation, invisible to the eye.

Regarding the extra cost of unfilled versus filled blocks, I would reconsider or consistently aim for the KfW 55 standard. In my opinion, anything less is neither here nor there. Because — you should save your “belief” for church, where it belongs.

Best regards, Bauexperte

fridolinmeier schrieb:
No, I haven’t. I think I will save up a bit over the years. However, it’s more important to me that I don’t have any cracks in the masonry or get any.

Hmm, I would have expected you to be more concerned about thermal bridges. What do cracks have to do with the cavity wall insulation and whether the insulation material "gets lost"?

Bauexperte schrieb:

Cracks are always possible over the years, regardless of the type of brick or block, since the house will settle. However, with careful planning of the foundation and site preparation, cracks can be minimized.

So, you mean a geotechnical survey and a “good” structural engineer?

The building ground is excellent. Limestone gravel, so it won’t settle anymore.

Hello,

fridolinmeier schrieb:
Building ground is excellent. Limestone gravel, so no further settling

Uh... Limestone gravel is relatively porous material? What is the groundwater level?

Regards, Bauexperte