Are cold corners in new buildings still contemporary?

Thank you! Is the 1-degree difference measured on you or is a 1-degree difference a value that should generally be achieved?

Measured when it was really cold.

May I quickly ask about the construction method of the house? Solid construction with or without external insulation / plaster / brick veneer?

With monolithic construction, the ceiling must then be executed with insulation strips, or how does that work? Actually an interesting question – also regarding lintels.

The (concrete) ceiling does not rest completely, but only partially. From outside to inside, it looks like this as far as I know: - edge ceiling stones (so that a uniform plaster base is created on the outside), e.g. 115mm - insulation, e.g. 110mm - concrete ceiling with bearing surface e.g. 200mm = total thickness 425mm For lintels, search for thermal insulation lintels or load-bearing roller shutter boxes, then the principle should become clear. Of course, I don’t know if everyone who builds monolithically implements everything so cleanly. I also don’t think there is a regulation for that.

The exterior corner, exposed to the weather on two sides, is a geometric thermal bridge. The thermal transmittance coefficient of the wall is calculated less favorably at this point because the wall thickness, measured diagonally into the exterior corner, increases, as does the heat flow that passes through the wall. Referring to 1m2 of interior wall surface in the corner, a greater amount of heat is released than through the same interior wall surface of the normal exterior wall. The difference, depending on the wall material used, lies between 25-40%.

It becomes problematic when the so-called "dew point" is fallen below at these spots. This is the temperature at which water vapor from the warm, humid indoor air condenses on cold surfaces. Keyword: cold mineral water bottle from the refrigerator on the summer terrace = condensation droplets form. The specific dew point depends on the room air temperature and the amount of water vapor contained therein (relative humidity). Under the standard indoor climate of 21°C/55% relative humidity, this dew point is, for example, 11.6°C, at 21°C/75% it is 16.4°C.

Normally, the temperature on the inside of the exterior wall should be only 2-3°C lower than the room air temperature (comfort factor). At about 18°C for the wall surface, a 25% reduced surface temperature in the corner situation means a temperature of 13.5°C. Here the dew point is fallen below at a relative humidity of 60%-65%. These climatic conditions are quickly reached in winter with insufficient ventilation/moisture removal. This leads to condensate formation and, in the long term, also to mold growth.

Which situation applies to you can only be assessed if the wall building material, wall thickness, and construction situation are known. New buildings must comply with the requirements of the Energy Saving Ordinance for heat-transmitting exterior components. The exterior corner will also always be cooler here unless additional thermal insulation is considered that specifically mitigates this point. Generally, the surface temperatures of a wall insulated according to the requirements of the Energy Saving Ordinance are not in this critical range under average climatic indoor conditions. However, user behavior plays a significant role here (heating/ventilation/room decoration + furnishing).

Very interesting post...
If I read that correctly, a combined system is therefore to be preferred in this regard?