What exactly is "well insulated"?

First of all, many thanks for your answers.

I will try to clarify my statements a bit.

Quote from zerogt:
Only Poroton is wanted by everyone.
Hardly. There are quite a few who build with aerated concrete, expanded clay, calcium silicate, pumice, or concrete.

Now that is somewhat vague, I was talking about the companies we have spoken to so far. And they all build with "Poroton."

Quote from zerogt:
At least KfW 70 via insulation, not technology
Then in my opinion the thickness of the roof insulation is already not right with all 3 providers ...

Ok. How thick should it be approximately?

Quote from zerogt:
3-gable house
12x9.5 Riegel on 1/3 of the garden side with a 1 m protrusion, so then 10.5
For a classic 3-gable house, the 3rd gable is quite small ... our comparable houses all have a depth of 3.00 m in the 3rd gable. What you describe I would rather call a dormer.

Alright then, let's agree on a dwarf gable. The provider talks about a Frisian house but the name we give it should not play a role.

A 16 cm ETICS I would currently consider "normal", if you decide on a house with ETICS; depending on the location and situation of the plot, both 17.5 cm exterior masonry and 24 cm blocks can fit.

The location is southeastern Lower Saxony in the triangle between Hanover, Braunschweig, and Hildesheim.

The house itself should be built in the old village center, so no edge-of-field location or similar.

Orientation of the house roughly with the dwarf gable (I am learning) to the southwest and unshaded.

These days there is a lot of talk about insulation, less about how certain KfW requirements can be met; this is not only achieved by additional insulation. Much still takes place "only" on paper; from my point of view, for example, heat recovery with ventilation systems. For me, this means you first have to decide what you want. Do you want to build a single-family house with ETICS or maybe a monolithic house, as "Doc" or "Manu" described? A statement like "I don't care how the heat is retained in the envelope" is, in my opinion, not very purposeful. Houses built with ETICS are generally cheaper ... although it does not always make sense to me; actually it should be the other way around.

Now with "I don't care for now," I mean that I am open to all suggestions.

Basically, the basic form offered is hollow brick + ETICS. I have my doubts whether it is wise to suddenly have the construction companies (all 3 execute the shell construction with their own employees) build with other materials. What use is the best filled block if it is processed incorrectly afterward?
If there are reasons against ETICS, I would of course like to hear them.

You also write that you do not want to heat with electricity—what do you understand by that? Do you want to build classically with a gas condensing boiler and solar heating support? Because "no matter what the KfW says" can only apply to you if you waive KfW funds; then only the currently valid Energy Saving Ordinance must be complied with.

Well, my basic idea is a gas condensing boiler + controlled residential ventilation with heat recovery to get the ventilation "problem" under control and for comfort reasons (several acquaintances rave about it). I actually do not want solar thermal.

KfW 70 is probably misleading on my part. The subsidy is not important to me; I just want to build a house that has a good compromise between construction costs and running costs. In other words, I do not want to have a super house on paper because it was made favorable, e.g., with a heat pump or pellet stove but actually still causes high heating costs.

Therefore, I want to find out up to which point it makes sense to insulate more and from where the effort begins to become disproportionately high compared to the benefit. Unfortunately, I do not know how to describe it better.

Our favorite is, for example, listed in the construction performance description as follows:

The windows specified as triple-glazed with a Ug of 0.6
Base plate 110 mm WLG 035
Walls 24 cm Poroton + 16 cm ETICS
Roof 20 cm mineral wool WLG 035

So, the question is where it makes sense to improve without, for example, investing 15,000 euros only to save 50 euros on gas afterward.

Best regards

Olli

Hello Olli,

Ok. How thick should it roughly be?

You want to work with a gas condensing boiler, so I think 240 mm will already be required. But you will only know for sure once Online Form 153 is created or, if KfW funding actually does not play a role, as soon as the energy certificate is to be calculated.

Location is southeastern Lower Saxony in the triangle between Hanover, Braunschweig and Hildesheim.

The wind whistles unrestricted over the land there :D

I have my doubts whether it is then wise to suddenly let the construction companies (all 3 build the shells with their own employees) build with different materials. What use is the best filled brick if it is processed incorrectly afterwards.

I would also urgently advise against that in any case. By the way, it is nowadays "normal" that the vast majority of construction companies build the shell with their own employees. Only starting with the carpenter do external craft businesses come into play.

If there are reasons now that argue against ETICS, I would of course like to hear them.

Me – stick my neck out again? No ...

I just want to find out up to which point it makes sense to insulate more and from when the effort starts to become disproportionately high compared to the benefit. Unfortunately, I don’t know how to describe it better.

Economically, today a KfW 70 efficiency house is reasonable; everything else is conviction or hobby … from my point of view….

Our favorite is, for example, listed as follows in the description of services

The windows 3-pane glazed with Ug 0.6 specified
Base plate 110mm WLG035
Walls 24cm Poroton + 16cm ETICS
Roof 20cm mineral wool WLG 035

Like most providers, your builder has succumbed to the competitor’s games. They specify the Ug value of the glass, but not the much more important value, namely the U-value. This refers to the value of the entire window. Also, as a client I would want to know which profiles (5 or more chamber profiles) or safety aspects (mushroom head locks) are installed.

By the way, the base plate specification only reflects the required values of the reference building. Our base plates show a value of 0.26 W(m2K) here but are also significantly thicker. It would be interesting in this context to know how the structure of the floor slab above the ground floor is designed. If you decide on a walk-in shower, do you have a visible "experience" under the room below?

So, and the question is where it still makes sense to improve without, for example, investing 15,000 euros to save 50 euros in gas afterwards.

If I read your data above, I think you will only know for sure when the house is calculated. As I already wrote, I find – but that is only my subjective impression – the value of the base plate and installed insulation not so great...

Rhineland regards