ᐅ Which House Concept? Fundamental Questions for Building a Home

Hello everyone,

We are fortunate to own a building plot and are now facing the difficult choice of how to proceed. For several months, we have been researching, visiting model homes, and actively reading forums. When it comes to layouts and features, opinions vary greatly, and depending on budget and taste, the possibilities seem endless.

But when it comes to the fundamental question of how to build today in an affordable, efficient, and above all healthy way, there should at least be a rough consensus! From everything we have read so far, we would probably prefer to build a Thoma house (36cm (14 inches) Holz100 walls), but financially that probably won’t be possible.

When we look for alternatives, we are often told that KFW40 (KFW40 / Passive House standards) is not achievable, that breathable construction is impossible, and that a mechanical ventilation with heat recovery system is absolutely necessary. Then, you keep searching and come across more “alternative” options like LowTec Bio Solar houses, which seems a bit too extreme for us.

We want to build a house free of harmful substances, and avoiding various materials is the best way to be sure that in a few years, nothing new will be found to be problematic. In this sense, a pure timber house does make some sense.

Then, the advice is that solar thermal systems are not worth it, so photovoltaic systems on the roof should be used instead. To make good use of that, a heat pump is necessary, and then air-to-air heat pumps are offered because geothermal with underfloor heating is so much more expensive. So, it’s either robbing a bank or making compromises.

And that’s exactly the kind of compromises we are looking for now. Who has chosen a particular building concept and for what reasons? Is a vapor barrier really necessary in the building envelope? Which heating and insulation technologies are still cost-effective today? And how do I create the healthiest possible indoor climate?

Thank you & best regards,
Luftpumpe

Why use a membrane? It only goes on the roof; you can’t do without it there.
Stone plus glass wool plus an air gap plus brick veneer is quite eco-friendly, in my opinion.

Indoor climate: old timber framing with clay plaster, which is supposedly the best.

We are very satisfied with our wall described above, which has conventional interior plaster and a controlled mechanical ventilation system.

What is your upper limit? It would be helpful to know in order to give advice.

Or just forget the marketing nonsense about being “healthy to live in” and build a normal house, like everyone else. By the way, walls don’t breathe either, as a second tip.

There is no consensus because everyone claims this nonsense to justify their own building material. Since no one knowingly uses prohibited substances, anyone can make that claim.

Wood inherently healthy to live in? Really, no adhesives or glues used? Electrical cables wrapped with love instead of insulation?

Basically, it’s possible, but your budget must be right. A price difference of 5,000–10,000 euros (about 5,500–11,000 US dollars) for the heating system is the least of your problems. Nothing off the shelf, everything special.

Oh dear, there is no right or wrong answer here.

Choose a focus area
Budget – energy saving regulations with gas and solar, window frame ventilation

Passive house – heat pump and controlled residential ventilation (window frame ventilation is not suitable). Solar panels make less sense with a heat pump, but photovoltaics obviously still do. The cost-effectiveness will not increase significantly due to the heat pump.

No vapor barrier in the wall, which rules out timber frame construction.

Healthy living construction – there are companies that offer this. Yes, your house will be almost free of formaldehyde and other harmful substances before moving in. Known harmful or discredited materials are avoided. That does not mean that tomorrow a substitute material won’t also be classified as hazardous. If you value this, you should consistently consider your furniture, decorations, clothing, and so on accordingly.

All of these aspects will exclude each other.

Building affordably and free of pollutants is a contradiction for me! I also don’t shop at organic markets or directly from farmers because it’s cheap there! Anything beyond the mass market is inherently expensive!

haydee schrieb:

No membrane in the wall, so timber frame is out

Since we build timber frames without a membrane, I have to disagree. By the way, we also build without a ventilation system, but that’s a matter of personal belief. Our company mainly constructs homes without ventilation systems, and that works without problems. I work from home anyway and can ventilate a lot whenever needed, so everyone has to decide for themselves.

Basically: Everyone has their own opinion on healthy living. Considering the climate protection aspect, we chose wood. The insulation material is also compressed wood. But the masonry camp (at least monolithic walls) also has good arguments, and you simply have to follow your own path.

Just be aware: If these points are important to you, it usually gets a bit more expensive.