Which stones are suitable for house construction?

Hello,

I have no idea about stones and don't know which are the best. You can find a lot of information on the WWW, but in my opinion, all stones are quite similar. Which stones are actually the best for thermal insulation and soundproofing? What thickness should one choose? Many also take slim stones and then add 5 cm of Styrofoam or something like that. What experiences have you had?

hello, I feel the same way. There is a lot of information on the internet about bricks and aerated concrete, I am also struggling with the decision of which stone to build with. In Bavaria Franconia, 90% of buildings are made with bricks, although bricks are more expensive than aerated concrete depending on the budget. Has anyone also gained experience with this?

Hello you two

Basically, you should first know what the respective energy certificate requires for the wall surfaces (depending on the house type and location.. or the wishes of the builder). ..after that, you can easily determine which wall thickness, with which material, would fundamentally meet these values.

You can also look around regionally, because not all stones can be delivered to all places in the country at the same price.

Also basically, the heavier the stone.. the more sound insulation it provides (although the question arises how high this would actually have to be and why?), which at the same time would be a disadvantage for thermal insulation.

For a purely load-bearing masonry, a 5 cm thick external insulation will of course never be sufficient today.... you should think in the range of 16-18 cm.

Most suppliers have the appropriate stones in their range to meet the current requirements for thermal protection. Some differ, however, in the variety of products or their shapes and supplementary stones. As long as the mason has a good stone saw at the construction site, the latter characteristic is no longer so decisive.

There are not so many material products.. suppliers/companies and brand names are more common. The most common products are probably aerated bricks (e.g. Poroton/Unipor...), aerated concrete (e.g. Ytong, Hebel..), pumice (e.g. Klimaleichtblock>KLB<, Iso-Bims, Pumix..) or the Liapor products... which are made from expanded clay pellets.

Ultimately, it is also a question of how and with what the local construction companies like to build.. what they know and therefore recommend.. There is usually no point in convincing the selected contractor of a product unfamiliar to him..

My tip: Start with the planning first.. the rest (possibly regarding the budget) usually follows by itself.

Hello, I also faced the problem and searched for the "best stone." I then asked masons from my circle of acquaintances, and one gave me a good answer or task. He said: Place a brick and a Ytong stone outside over the winter and then see which one is better preserved after the winter. I decided on the Ytong stone because it absorbs little moisture and therefore is less damaged by frost/thaw cycles. Another advantage I noticed was that less moisture arises during the construction phase from gluing the stones. You also get a good smooth surface inside and outside, which saves money when cleaning the house. So I chose the 36 cm without insulation and am fully satisfied. Better to properly insulate the roof, because heat rises upwards as is well known, and let the house breathe at the walls. Best regards Dachspezi

Hello Dachspezi

In the end, you have chosen the most absorbent stone (Ytong=autoclaved aerated concrete)..whatever your "winter self-test according to a well-known mason's recommendation" actually showed? In this respect, I simply consider your statement: "That it absorbs little moisture" to be wrong! What do you understand by "tauwechsel"???? I haven't heard this term before..

That a thin-bed mortar (that's what you called the stones "glued") introduces less moisture has nothing to do with the building material "aerated concrete".. this is the same for ALL other products compared to mortar masonry!

It also does not save a single cent if an aerated concrete block is used for plastering work (because of a smoother surface). This product must be treated with a thin coat of plaster and/or with an appropriate primer due to the too high absorbency, for a normal interior plaster (which will/can mean additional costs). So, no price advantage as you suggested here.

Insulation values must be met not only by the roof surface but of course also by the walls... the ground floor walls naturally release their heat to the outer shell... and not to the roof surface.. and walls "cannot breathe"...! If they could, they would need lungs.. they don't have them.. so they don't breathe! You better refrain from such expressions.. they are technically wrong.

Just to clarify.. of course, aerated concrete products can be used, like many others as well... as explicitly requested in this thread.

Hello BauLine,

since I am – as you probably know – a big fan of aerated concrete, I cannot just leave your answer as it is without further explanation.

In the end, you chose the most absorbent stone (Ytong=aerated concrete)...

For a pleasant, healthy indoor climate, the humidity of indoor air must be limited. Relative humidity levels of 50–60% are considered optimal from a medical point of view. Indoor climates with up to 70% relative humidity are still perceived as comfortable by people. At even higher humidity levels, the indoor air is usually perceived as stuffy and the risk of moisture damage at thermal bridges or mold growth on the wall surface increases. Already at a relative humidity of about 80% — in areas of thermal bridges even only 60% — noticeable mold growth can begin on the wall surface after a few days. The breeding ground is inevitable deposits of house dust. The consequence of this is health-endangering spore concentrations in the indoor air. Even with normal use, the occurrence of moisture peaks, such as those caused by cooking or showering, cannot be prevented. However, through building materials with a high moisture buffering capacity, these moisture peaks can be dampened below 80% relative humidity. Aerated concrete is the wall building material with the highest moisture buffering capacity.

Due to its pore structure, aerated concrete is able to quickly absorb large amounts of moisture from the air and release it again. This effectively buffers peaks of relative humidity, e.g., after cooking or showering, and almost excludes the risk of mold formation. This does not mean that residents can forgo regular ventilation of their apartments. However, the indoor climate becomes more robust and ventilation errors are more easily tolerated.

Source: M. Reick, M. J. Setzer: Investigation of the sorption behavior of materials enclosing living spaces, building physics of exterior walls, 1998.

Kind regards