Ytong Energy Saving Regulation 25cm stone thickness allowed - Who has experience?

Energy Saving Ordinance, renovation of existing buildings, max 50 sqm without new heating: orientation towards the existing building. You can google this:

You can also google Chemtrails and tin foil hats and you will find some really well-documented statements on those.

But if you simply look at the freely accessible Energy Saving Ordinance 2014 (2016 only changed the tightening of 25% of the primary energy demand in new buildings compared to 2014), you will find under §9 sentence (4): When expanding and extending a building by heated or cooled rooms for which no heat generator is installed, the affected exterior components must be altered or constructed so that the heat transfer coefficients of the affected surfaces do not exceed the maximum values of the heat transfer coefficients specified for such exterior components in Annex 3. If the newly added contiguous usable area is larger than 50 square meters, the requirements for summer thermal protection according to Annex 1 number 3 or Annex 2 number 4 must also be met.

A hut built around 1950 from double brick rows without insulation logically MUST NOT be extended with "orientation towards the existing building."

I did some "research": The most common size of Ytongg stones is certainly a length of 62.5 centimeters and a height of 25 centimeters. However, there are numerous other sizes: • Ytongg stones are available in lengths of 33.2 cm, 39.9 cm, 49.9 cm, 59.9 cm, and 64.4 cm. • Besides different lengths, we also have a choice in the height of the stones. They come in heights of 19.9 cm and 24.9 cm. (20/25) • For every construction project, Ytongg stones are also available in various thicknesses. The sizes offered are 5 cm, 7.5 cm, 10 cm, 12 cm, 15 cm, 20 cm, 25 cm, 30 cm, and 36.5 cm. • If we use so-called Thermoblocks (price?), we can do without additional insulation because of the good thermal insulation of these stones. These Thermoblocks are available in lengths of 50 cm and 62.5 cm. In width, 30, 40, and 50 cm are available; the height of these stones is always 20 cm. So the recommended Thermoblocks are not available in the 25 cm width I want. The 25 cm stone has a U-value (plastered) of 0.48 W/m²K. This falls below the values required by the Energy Saving Ordinance. If building without subsidies, it apparently is not properly checked, because the overall values (lambda) of the house also play a role. That means windows and the type of heating are included in the overall house value. As a result, some have definitely managed with 25 cm and 30 cm stones, and if you live in the house yourself and do not rent it out, you do not need an energy certificate, which would reveal it during its creation. Everything is apparently a bit "vague." When I have worked through it, I will post an update. Since I have already started to inform myself about heating alternatives (heat pump), as the oil price hit me hard this year, I realize that I could almost pursue a new degree. No more free time ;-)! Greetings to all "builders"

Just as an idea from a layperson: If you need 25 cm wide Ytong blocks, but they are not available in this width – however, there are blocks in 50 cm width – then just borrow a cutting machine (for example, we borrowed one from our shell builder) and cut them in half.

Or are there then problems with the statics of the blocks? We only did this on a small scale for a non-load-bearing wall for the shower shelf. You would just need to know if there are ring beams in this size for the load-bearing walls.

For space reasons, the walls should be as thin as possible? Then a monolithic Y-Tong construction might generally not be optimal. What speaks against a timber frame construction or KS with [WDVS]?

The question is also to what extent the actual construction will ever be inspected as long as it is built at the approved location and complies with clearance areas, etc. ([Application] with slightly thicker stones, but actually executed with your preferred stones....)

There are 25 cm blocks, which I want to use for space reasons, the question was to what extent these can be used. Statics-wise, it is no problem. The energy saving ordinance was the question! You will certainly be right that if no funding is used, no one checks afterward anymore. There is nothing against the use of other building materials. My reason is: I have already built with it, it worked great, like Lego. Fast and clean, because of adhesive and no mortar quantities and as a "non-mason" that is a relief. Greetings to all DIY builders

Do it, no long talking, head back and go.